This appeal from the grant of summary judgment in favor of antitrust defendants presents a familiar pattern. A dealer irritates his competitors and their principal supplier through his aggressive price discounting practices. The other dealers complain to the supplier, who, to placate the aggrieved dealers, agrees not to sell any product to the dealer. The "boycotted" dealer then brings a Sherman Act suit, 15 U.S.C. § 1 et seq., in federal court. The alleged conspiracy involves a number of the plaintiff's competitors, and the refusal to deal is said to have become a group boycott, which can be a horizontal antitrust violation with per se antitrust implications; the supplier, notwithstanding its vertical relation to the plaintiff, is said to have become a co-conspirator.

The present case arose out of the rough and tumble roofing and siding materials distribution business in northern New Jersey, where several favored roofing and siding distributors were concerned that the entrance of a new price cutting competitor could destabilize the market and substantially cut into their profit margins. The principal players in this drama are plaintiffs Joseph Rossi, and his two successive roofing and siding distribution businesses, Rossi Florence Corp. ("Rossi Florence"), and Rossi Roofing, Inc. ("Rossi Roofing"); defendants Standard Roofing, Inc., ("Standard") and Arzee Supply Corporation ("Arzee"), two of Rossi's chief competitors, and several of their key officers; and defendant GAF Corporation ("GAF"), the manufacturer that supplied the most important product in the market. Minor roles were played by defendants Wood Fiber Industries, Inc. ("Wood Fiber"), another roofing and siding manufacturer, and Servistar Corp. ("Servistar"), a national purchasing cooperative and reseller of roofing and siding products.

Following discovery, the district court granted summary judgment for all defendants on the ground that plaintiffs had failed to adduce sufficient evidence to meet the demanding standard of proof in the antitrust context established by the Supreme Court's jurisprudence. The court also relied on plaintiffs' alleged failure to demonstrate causation and damages. While we agree with the district court that Rossi cannot survive summary judgment as to Servistar and Wood Fiber, we believe that the record is sufficient to enable Rossi to survive summary judgment on the antitrust claims as to Standard, Arzee, the individual defendants associated with those firms, and GAF.

The Supreme Court's jurisprudence in the area of concerted refusals to deal teaches that not every situation in which a distributor is cut off at the behest of his competitors constitutes a group boycott entitled to per se treatment. Otherwise, legitimate efforts by manufacturers to impose reasonable rules limiting intra-brand competition would be outlawed and the beneficial effects such actions have on inter-brand competition would be lost. Moreover, the distinction between vertical and horizontal restraints would blur. These concerns, however, are not implicated here, in view of both the price-related orientation of the alleged offending conduct of the key defendants and the sheer scope and draconian modus operandi of the alleged conspiracy.

The jurisprudence also renders it difficult for an antitrust plaintiff to prove that the manufacturer and distributors conspired, typically because it is difficult for the plaintiff to demonstrate that what the manufacturer or supplier did was inconsistent with independent action or that the claimed conspiracy makes economic sense. In this case, however, at least at the summary judgment stage, that burden is surmounted by the presence of certain direct evidence of conspiracy as well as: (1) evidence that GAF acted against its consistent policy (and hence ostensibly against its own interest) in refusing to sell (and seeing to it that others did not sell) GAF products to Rossi; (2) evidence of pretext in connection with GAF's efforts to explain away the foregoing; (3) evidence that the major suppliers had sufficient leverage over GAF to induce it to so act; and (4) the quite graphic and extensive nature of the statements and actions of various defendants directed towards eliminating Rossi as a price-cutting competitor who passed secret rebates onto his customers and thereby threatened to de-stabilize the market. We also discern genuine issues of material fact on causation and damages, and this too precludes summary judgment on the antitrust claims against the key defendants.

Although the district court's order granting summary judgment on the antitrust claims regarding GAF, Standard, Arzee, and their corporate officers must be reversed, it must be affirmed as to Servistar and Wood Fiber, since Rossi has failed to overcome his burden of showing that either Servistar's or Wood Fiber's actions tended to exclude the possibility of independent action on their part. More specifically, Rossi has failed to put forth any evidence of Servistar's motive to conspire; as we shall explain, Servistar's relationship to GAF was far different from that of the distributor defendants. Rossi has also failed to show that the other defendants had any leverage over Servistar with which they could have coerced it to join the conspiracy. With respect to Wood Fiber, the only evidence Rossi has been able to adduce is that Wood Fiber may, on one or two occasions, have responded to pressure and threats from Standard and Arzee by not selling to Rossi, and hence this record is insufficient to satisfy the standards for proving concerted action as delineated by the Supreme Court.

Rossi also pressed a tortious interference claim under New Jersey state law. The district court granted summary judgment for all defendants on this claim without any discussion. This aspect of the judgment must be set aside because it violates our rule requiring that district courts accompany grants of summary judgment with an explanation sufficient to permit the parties and this court to understand the legal basis for the court's order. See Vadino v. A. Valey Eng'rs, 903 F.2d 253, 257-60 (3d Cir.1990).

The following background facts, which describe the basic framework and background within which this case arises, are set forth in the light most favorable to the non-moving party as is required when considering a motion for summary judgment. The remainder of Rossi's evidence, most of which deals specifically with the existence vel non of concerted action by the defendants, will be detailed in § II.B.2, infra, after we have explained the appropriate legal standards.

The plaintiffs, in addition to Joseph Rossi, are Rossi Florence and Rossi Roofing.1 Rossi has been in the roofing and siding distribution business in northern New Jersey since 1972. Rossi Florence and Rossi Roofing were roofing and siding distribution companies formed by Rossi at the end of 1988 and the beginning of 1989. Both are now out of business. This suit was brought against a number of Rossi's competitors (as well as several individuals associated with them), several roofing and siding manufacturers, and one national purchasing cooperative. Several of the original defendants, Allied Roofing, Inc. ("Allied"), Nailite Corp. ("Nailite"), Certainteed Corp. ("Certainteed"), and Wolverine Technologies Corp. ("Wolverine") have settled with Rossi and were dismissed from the case. The remaining defendants are: Standard, Arzee, GAF, Wood Fiber, Servistar, the estate of Robert Higginson (hereinafter "Robert Higginson"), William Higginson, Joseph Licciardello, Alvin Roth, and Cary Roth.

Standard and Arzee are distributors of roofing and siding products in northern New Jersey. Like Rossi Roofing, they purchase products from manufacturers and resell them to contractors and applicators in large volume. Standard is headquartered in Tinton Falls, New Jersey and has seven branch locations, including five in New Jersey, one in Pennsylvania, and one in Connecticut. Robert Higginson was the founder and chairman of Standard. William Higginson, Robert's son, is a shareholder and the current president of Standard. Arzee is a family-owned distributor with one of its branches located adjacent to Standard in Cedar Knolls. Defendant Alvin Roth is a shareholder and the president of Arzee, and defendant Cary Roth is Alvin's son and one of Arzee's branch managers.

GAF and Wood Fiber manufacture and supply roofing products to distributors like Rossi Roofing, Standard, and Arzee. GAF and Wood Fiber are two of the 37 roofing product manufacturers that serve the northern New Jersey market. GAF manufactures and sells its roofing material ("GAF product") to most, but not all, of the distributors located in northern New Jersey. GAF sold to Standard, Arzee, and Allied, but refused to sell to Rossi. Joseph Licciardello was an employee of GAF, who quit his job and replaced Rossi as vice president of Standard after Rossi was fired.2 Wood Fiber competes with GAF in the northern New Jersey market, manufacturing and selling Structodek FS, a product used principally in commercial roofing applications.

Defendant Servistar is a member-owned, national purchasing cooperative that operates hardware distribution centers nationwide. Servistar has over 4000 members at the retail level and deals primarily in paint, hardware, plumbing and electrical supplies, housewares, lawn and garden equipment, power tools, and lumber. Roofing products account for only 2% of Servistar's total purchases on behalf of its members, which were just under $1 billion in 1990. Servistar does not warehouse roofing supplies, but rather operates on a "drop shipment" basis, meaning that members place their orders through Servistar (which affords them a discount based on Servistar's status as a national volume purchaser), and the selected roofing manufacturer then supplies the product directly to the member. Servistar pays the manufacturer and later collects from the member.

B. Rossi at Standard; Rossi Forms His Own Company

From 1972 to 1988, Rossi worked for defendant Standard as the manager of its Cedar Knolls, New Jersey branch, selling roofing and siding materials. In 1980, Rossi was promoted to vice president, rewarded with stock in the company, and told that he would eventually become a co-owner of the business. Eight years later, however, in September 1988, Standard fired Rossi. The parties dispute the reasons for Rossi's discharge. Rossi alleges that Standard fired him because he refused to participate in a conspiracy with defendant Arzee to fix prices, discussed infra at § II.B.2.a. Standard claims that it fired Rossi for a combination of reasons including his deteriorating work performance, his failure to control expenses, the Cedar Knolls branch's excessively high payroll expenses under his management, his large personal expense account, his failure to arrive at work until late morning, his concentration on outside business ventures to the detriment of Standard, and, ultimately, his failure to achieve branch profits commensurate with branch sales.

At all events, by the time he was fired, Rossi had developed a reputation within the industry for extremely competitive pricing, excellent service, and reliability. While at Standard, Rossi had refined an aggressive marketing strategy that stressed high volume sales at low prices. This strategy, as one might imagine, angered Rossi's competitors and even concerned some of his suppliers, which were sensitive to their distributors concerns about pricing.

After his termination, Rossi decided to use his connections within the industry to open his own roofing and siding distributorship that would serve northern New Jersey in direct competition with Standard and Arzee. Rossi's first attempt, in late 1988, was Rossi Florence, a joint venture with Richard Droesch ("Droesch"), president of Florence Corp. ("Florence"), a roofing, siding, and window distributor in Long Island, New York. Rossi and Droesch planned to operate their new business out of a warehouse Rossi owned at 8 Frederick Place, located immediately adjacent to Standard's Cedar Knolls/Morristown branch and just down the street from Arzee's Morristown branch. Rossi and Droesch made substantial preparations for their venture during the fall of 1988. Droesch (together with one of his employees) invested $100,000 in Rossi Florence, and Rossi Florence obtained a $900,000 bank line of credit secured by the principals' personal guarantees. By mid-January 1989, however, Droesch decided to pull out of Rossi Florence, and Rossi refunded his investment. Droesch felt that because of pressure from Standard, Arzee, and others, the new company would be unable to get the products it needed to successfully compete in the market. In addition, Alvin Roth, president of Arzee, threatened Droesch that if he continued in business with Rossi in New Jersey, Arzee would open up a branch in Long Island to compete directly with Droesch's Florence distributorship.

Thereafter, in February 1989, Rossi incorporated Rossi Roofing, continuing his efforts to break into the roofing and siding distribution business in northern New Jersey. Rossi Roofing obtained another $900,000 bank line of credit, personally guaranteed by Rossi and his wife. The company, which opened for business on March 20, 1989, closed in less than a year, after experiencing great difficulty in obtaining product lines and weathering the brunt of a major downturn in the New Jersey housing industry. In January 1990, unable to run Rossi Roofing profitably, Rossi sold the company's assets to American Builders and Contractors, Inc. ("ABC"), a national roofing and siding distributor.

C. The Roofing and Siding Industry in Northern New Jersey; Price Discounting and Market Shares

During the relevant time period, the northern New Jersey market included thirty-nine roofing distributors with more than fifty-seven locations. Eleven residential roofing manufacturers, nine commercial roofing manufacturers, and seventeen vinyl siding manufacturers operated in the region. It is undisputed that this roofing and siding marketplace was highly competitive, and that roofing and siding contractors constantly price-shopped, pitting distributor against distributor in order to obtain the best possible deal.

GAF, which served this region, offered certain favored distributors secret off-invoice, volume and non-volume discounts or "rebates" in the form of periodic credits against purchases. Standard, Arzee, and former defendant Allied purportedly all received such discounts from GAF. The amount of these discounts was kept highly confidential because the favored distributors feared that if other distributors found out, they might complain to GAF and ultimately destabilize prices in the market. As GAF district sales manager Elmer "Bud" Krusa put it, "the less people that know about it, the less chance you have of getting it--dropping the entire market price." Rossi contends that while he was employed at Standard, he would pass these discounts on to his customers in an effort to increase his market share, whereas his competitors typically pocketed the rebate.

GAF and Wood Fiber are the only two manufacturers remaining as litigants in this case. According to GAF's own estimates, it supplied a large percentage of the New Jersey shingle market (38% for all shingles and 71% for laminate shingles). GAF was Standard's primary supplier of roofing products in the 1980's, and Standard was GAF's biggest customer in New Jersey and one of its top five customers in the entire country. Standard bought $7.7 million of GAF product in 1989 (or 32% of GAF's total sales in New Jersey that year), substantially more than any other GAF customer in New Jersey.

Arzee and former defendant Allied also purchased GAF product, but in markedly smaller quantities. Arzee, for example, featured Tamko and Owens Corning Roofing, rather than GAF product, and only purchased $919,747 of GAF product in 1989 (or 4% of GAF's total sales in New Jersey in 1989). Together, however, Standard, Arzee, and Allied (which bought $2.1 million of GAF product in 1989) purchased $10.7 million of the $24.1 million of GAF product sold in New Jersey (or 44% of GAF's total sales in New Jersey in 1989).3 Rossi contends that, notwithstanding the large number of other manufacturers offering product in the area, GAF product was critical for a distributor to successfully compete in Northern New Jersey, as evidenced by GAF's large market share and also the fact that it was the most desirable and popular roofing material available. This in turn stems in part from several facts: GAF product was well-known by both homeowners and contractors; GAF guaranteed its product; and importantly, GAF product had already been selected for many of the existing townhouse projects in northern New Jersey in 1989 and 1990, making it impossible for the builders to switch brands mid-stream.

The evidence in the record regarding Wood Fiber's market position in 1989-90 is not as clearly defined as that of GAF. Wood Fiber manufactures Structodek FS, a commercial roofing product used primarily in commercial applications for certain modified bitumen roofs. Commercial work comprised no more than a third of Rossi Roofing's business; the remaining two-thirds consisted of residential roofing. We do not know from the record how much product Wood Fiber sold in the northern New Jersey market; nor do we know what percentage of Wood Fiber's sales was purchased by Standard or Arzee (or Allied); nor is there any evidence that Wood Fiber had an off-invoice rebate program favoring certain distributors similar to GAF's. This is not surprising because Wood Fiber's involvement in this case stems largely from two isolated episodes, one in which a Wood Fiber representative complained of "pressure" not to sell to Rossi Roofing, and another in which Wood Fiber refused to supply product to Rossi after having accepted an order. See infra § II.B.2.d.

Rossi submits that because of his inability to purchase "GAF and other essential products, Rossi Roofing could not succeed." Unable to sustain the business any longer, on January 8, 1990, Rossi entered into an asset purchase agreement with ABC, which leased Rossi's 8 East Frederick Place property and opened a branch where Rossi Roofing once stood. Most employees, including Rossi as the branch manager, continued to work for ABC. According to Rossi, ABC (which was able to get GAF and other products) did very well. In 1990, it achieved over $5.5 million in sales, and by 1993, sales had increased to $11 million.4 In 1993, ABC fired Rossi, closed the Morristown branch, and transferred operations to Randolph, New Jersey. Rossi then entered into a similar agreement with Allied, which opened up a location on Rossi's property and hired him to manage it.

Rossi contends that he suffered substantial damages when Rossi Florence and Rossi Roofing, unable to get GAF and other important products, failed. In support, Rossi offers the testimony of several of his former customers during his tenure at Standard, who stated that they would have done business with Rossi Roofing if it had had the necessary product lines. Thus, in Rossi's submission, if the manufacturers had sold to him the same products that they ultimately sold to ABC (and later Allied), Rossi Roofing would have succeeded, and "over time, Rossi would have had his company open up new branches, as Standard, Arzee and Allied have done. The lost profits to Rossi Florence, and to Rossi Roofing, have been over $7 million at a minimum." In addition, Rossi claims to have suffered additional, non-duplicative damages of over $1 million from payments he made on behalf of Rossi Florence and Rossi Roofing, including payments made on his personal guarantees of Rossi Roofing's debts.

Rossi's action in the district court alleged, inter alia, a group boycott in violation of Section 1 of the Sherman Act, 15 U.S.C. § 1, and Section 3 of the New Jersey Antitrust Act, as well as tortious interference with plaintiffs' contractual and prospective contractual relations.5 After extensive discovery and submissions in support of and opposition to the motions, the district court granted defendants' motions for summary judgment, finding insufficient evidence of concerted action, causation, and damages. Rossi has appealed not only that judgment but also a discovery ruling--the district court's order denying a motion to compel defendant GAF to provide additional factual detail about the subject matter of GAF's counsel's handwritten notes of three telephone conversations with GAF employees.

The district court had subject matter jurisdiction pursuant to 28 U.S.C. §§ 1337 and 1367, as well as 15 U.S.C. § 15. We have appellate jurisdiction pursuant to 28 U.S.C. § 1291.

Under the literal dictates of § 1 of the Sherman Act "every contract, combination in the form of trust or otherwise, or conspiracy, in restraint of trade or commerce ... is declared to be illegal." 15 U.S.C. 1 (emphasis supplied). The Supreme Court has interpreted this provision to prohibit only unreasonable restraints. See Business Elecs. Corp. v. Sharp Elecs. Corp., 485 U.S. 717, 723, 108 S. Ct. 1515, 99 L. Ed. 2d 808 (1988). To determine whether a restraint is unreasonable, courts apply one of two modes of analysis, depending upon the nature of the concerted action at issue. Agreements are either analyzed through "a case-by-case application of the so-called rule of reason," whereby the fact finder "weighs all of the circumstances of a case in deciding whether a restrictive practice should be prohibited as imposing an unreasonable restraint on competition," id. (internal quotations omitted), or the court applies the per se standard, which dispenses with the need for case-by-case analysis.6 See id. Under the per se standard, conduct that is "manifestly anticompetitive" or "would always or almost always tend to restrict competition," id. (internal citations omitted), is conclusively presumed to unreasonably restrain competition "without elaborate inquiry as to the precise harm [it has] caused or the business excuse for [its] use." Northern Pac. Ry. v. United States, 356 U.S. 1, 5, 78 S. Ct. 514, 2 L. Ed. 2d 545 (1958). This is because "of [its] pernicious effect on competition and lack of any redeeming virtue." Northern Pac. Ry., 356 U.S. at 5, 78 S. Ct. 514. Thus, the first issue we must consider is whether the conduct alleged here warrants per se or the more lenient rule of reason treatment, because that determination will dramatically affect the quantum of proof Rossi must offer to sustain his claim.

A. Characterizing a Group Boycott; Per se Versus the Rule of Reason

Rossi, relying on such cases as United States v. General Motors Corp., 384 U.S. 127, 86 S. Ct. 1321, 16 L. Ed. 2d 415 (1966), Big Apple BMW, Inc. v. BMW of N. Am., Inc., 974 F.2d 1358, 1376 (3d Cir.1992), Fragale & Sons Beverage Co. v. Dill, 760 F.2d 469, 473 (3d Cir.1985); Malley-Duff, 734 F.2d at 140, and Edward J. Sweeney & Sons, Inc. v. Texaco, Inc., 637 F.2d 105, 114 (3d Cir.1980), alleges that the defendants engaged in a classic horizontal group boycott that qualifies as a per se violation. Rossi submits that several of his fellow distributor-competitors (i.e. Standard, Arzee, and Allied), as well as their principal manufacturer/supplier(s), agreed to boycott Rossi Florence and Rossi Roofing and frustrate Rossi's attempts to obtain the products he needed to successfully compete against them.

Defendants respond that Rossi's theory does not comprise a per se antitrust claim because it is a vertical conspiracy in which there has been no allegation of resale price fixing. We agree with defendants that if this were simply a vertical conspiracy, between one horizontal competitor and one supplier or manufacturer, we would analyze it under the rule of reason unless there were some evidence of price fixing. See Business Elecs., 485 U.S. at 735-36, 108 S. Ct. 1515 (analyzing an alleged agreement between one supplier and one horizontal distributor as a vertical non-price-fixing conspiracy under the rule of reason); Tunis Brothers, 763 F.2d at 1497, 1502 (same); cf. Continental T.V., Inc. v. GTE Sylvania, Inc., 433 U.S. 36, 37, 59, 97 S. Ct. 2549, 53 L. Ed. 2d 568 (1977) (concluding that franchise agreements that bar retailers from selling franchised products from locations other than those specified are analyzed under the rule of reason).7 Unlike the cases cited above, however, here there are a number of horizontal competitors involved. Thus, this case more closely resembles the horizontal nature of United States v. General Motors Corp., 384 U.S. 127, 86 S. Ct. 1321, 16 L. Ed. 2d 415 (1966), a case that the Supreme Court treated as a group boycott with per se implications.

In General Motors, the Supreme Court found a group boycott where a group of automobile dealers had joined together to force their manufacturer, General Motors, to assist them in ending the practice of some dealers that were reselling their automobiles to discounters. See id. at 143-44, 147, 86 S. Ct. 1321. Other cases fit this mold as well. See, e.g., Big Apple BMW, 974 F.2d at 1376 (analyzing an alleged agreement among supplier BMW North America and several of its dealers to prevent a potential price-cutting competitor from receiving a franchise as a horizontal group boycott); Sweeney, 637 F.2d at 114 (holding that when a manufacturer terminates a distributor's supply pursuant to an agreement with several distributors, these actions make out a horizontal § 1 claim); cf. Klor's, Inc. v. Broadway-Hale Stores, Inc., 359 U.S. 207, 212-13, 79 S. Ct. 705, 3 L. Ed. 2d 741 (1959) (applying a similar horizontal analysis under § 2 of the Sherman Act where manufacturers and distributors had conspired among themselves and with a major retailer to deprive another retailer access to product lines).

The common principle we glean from these cases is that a conspiracy is horizontal in nature when a number of competitor firms agree with each other and at least one of their common suppliers or manufacturers to eliminate their price-cutting competition by cutting his access to supplies. From this perspective, Rossi's asserted conspiracy is indistinguishable from those put forth in General Motors, Klor's, Big Apple BMW and Sweeney--namely, "joint action to eliminate [a] discounter[ ] from participation in the market," General Motors, 384 U.S. at 144, 86 S. Ct. 1321--and thus, the defendants' characterization of the conspiracy Rossi alleges as vertical, and not horizontal, cannot withstand scrutiny.

This conclusion, however, leaves us with the second (and ultimately more difficult) question whether this horizontal agreement, which Rossi labels a "group boycott," qualifies as a per se violation. Traditionally, such agreements have received such per se treatment. See Malley-Duff & Assocs. v. Crown Life Insur. Co., 734 F.2d 133, 140 (3d Cir.1984). Indeed, in all of the horizontal "group boycott" cases listed above, the court adopted the per se approach. See, e.g., General Motors Corp., 384 U.S. at 143-44, 147, 86 S. Ct. 1321; Klor's, 359 U.S. at 212-13, 79 S. Ct. 705; Big Apple BMW, 974 F.2d at 1376; Sweeney, 637 F.2d at 114. More recently, however, the Supreme Court has reminded us that it is not a simple exercise to determine what conduct falls within the "forbidden category" of a per se group boycott. See Northwest Wholesale Stationers, Inc. v. Pacific Stationery & Printing Co., 472 U.S. 284, 294, 105 S. Ct. 2613, 86 L. Ed. 2d 202 (1985) (" '[T]here is more confusion about the scope and operation of the per se rule against group boycotts than in reference to any other aspect of the per se doctrine.' ") (quoting L. Sullivan, Law of Antitrust 229-30 (1977)); FTC v. Indiana Fed'n of Dentists, 476 U.S. 447, 458-59, 106 S. Ct. 2009, 90 L. Ed. 2d 445 (1986). Under the more recent jurisprudence, it is clear that assigning the label "group boycott" to a concerted refusal to deal with a distributor does not have a talismanic effect, automatically bringing the case under the per se rubric. Instead, the Supreme Court has directed us to carefully scrutinize the nature of the asserted refusals to deal to determine whether it fits within the per se " 'boycott' pigeonhole." Indiana Fed'n of Dentists, 476 U.S. at 458, 106 S. Ct. 2009.

In Northwest Wholesale Stationers, the Supreme Court attempted to explain what kinds of boycotts qualify for the per se approach and what kinds do not. The Court emphasized that the per se approach was appropriate when the allegations were of "joint efforts by a firm or firms to disadvantage competitors by either directly denying or persuading or coercing suppliers or customers to deny relationships the competitors need in the competitive struggle." 472 U.S. at 294, 105 S. Ct. 2613 (internal quotes omitted). The Court also noted that per se boycott cases usually contain three elements: "denial of something a competitor needs to compete effectively, defendants with a dominant position in the relevant market, and the absence of any plausible contention that the challenged behavior would 'enhance overall efficiency and make markets more competitive.' " P. Areeda & H. Hovenkamp, Antitrust Law p 1510 (Supp.1997) (quoting and interpreting Northwest Wholesale Stationers, 472 U.S. at 294-95, 105 S. Ct. 2613). Finally, the Court instructed that although "a concerted refusal to deal need not necessarily possess all of these traits to merit per se treatment ... [a] plaintiff seeking application of the per se rule must present a threshold case that the challenged activity falls into a category likely to have predominantly anticompetitive effects. The mere allegation of a concerted refusal to deal does not suffice because not all concerted refusals to deal are predominantly anticompetitive."8 Northwest Wholesale Stationers, 472 U.S. at 295, 298, 105 S. Ct. 2613.

Applying these precepts to the "boycott" at issue in Northwest Wholesale Stationers, the Court determined that it was "not a form of concerted activity characteristically likely to result in predominantly anticompetitive effects." Id. at 295, 105 S. Ct. 2613. In that case, a retail office supply store had sued a nonprofit cooperative buying association claiming that its expulsion from the cooperative was per se illegal. The expulsion--without explanation, notice, or hearing--hurt the plaintiff by effectively raising the wholesale price of supplies and eliminating certain favorable warehousing options made available to members of the defendant. Examining this type of restraint, the Court held that "[t]he act of expulsion from a wholesale cooperative does not necessarily imply anticompetitive animus and thereby raise a probability of anticompetitive effect." Id. at 296, 105 S. Ct. 2613 (citations omitted). Rather, the Court noted that cooperatives must "establish and enforce reasonable [membership] rules in order to function effectively." Id. Therefore, the rules that the plaintiff allegedly violated (it allegedly failed to disclose to the cooperative membership of a change in its ownership) might have been necessary for the cooperative to monitor its members' creditworthiness. Without a showing that "the cooperative possesse[d] market power or exclusive access to an element essential to effective competition," the Court held that expulsion based upon violation of the disclosure rules was not "likely to result in predominantly anticompetitive effects." Id.

Similarly, in Indiana Fed'n of Dentists, the Court refused to extend per se group boycott status to a situation in which a professional association collectively refused to cooperate with insurers' requests for x-rays. The Court refused to expand the category of cases classified as per se group boycotts to situations involving professional associations or situations where "the economic impact of certain practices is not immediately obvious." 476 U.S. at 459, 106 S. Ct. 2009. While the collective refusal to cooperate with insurers "resemble[d] practices that have been labeled 'group boycotts,' " the Court refused to hold that the economic impact of this agreement was immediately obvious. Id. at 458, 106 S. Ct. 2009.

Here, in contrast to Indiana Fed'n of Dentists and Northwest Wholesale Stationers, the defendants are not members of a professional association, and the economic impact of their actions--driving a price-cutting competitor out of business--is clear. Applying the precepts laid out in Northwest Wholesale Stationers, we believe that the Rossi boycott falls within the description of "joint efforts by a firm or firms to disadvantage competitors by either directly denying or persuading or coercing suppliers or customers to deny relationships the competitors need in the competitive struggle." 472 U.S. at 294, 105 S. Ct. 2613 (internal quotes omitted). As will be discussed more fully below, see infra § II.B.2.b(1), Rossi has adduced evidence that GAF product was, if not unique, then at least necessary for him to compete in the marketplace. Further, the gravamen of his complaint fits snugly within the Court's Northwest Wholesale Stationers description of per se concerted refusals to deal--namely, Standard and Arzee (and perhaps other horizontal competitors like Allied) conspired with manufacturers like GAF and suppliers like Servistar to deny Rossi access to GAF product as well as to coerce other suppliers not to sell any products to him. Importantly, all of this activity was done against the backdrop of Standard's and Arzee's dissatisfaction with Rossi's price-cutting proclivities, and thus an inference can be drawn that the conspiracy was at least partially conceived as a price restraint.

For these reasons, we find it implausible that the alleged behavior by the defendants would "enhance overall efficiency and make markets more competitive," Northwest Wholesale Stationers, 472 U.S. at 294, 105 S. Ct. 2613, and therefore, taking into account the Court's most recent guidance, we conclude that Rossi's allegations should be analyzed using the per se framework.

Our conclusion that Rossi's allegations constitute a per se violation of § 1 simplifies our analysis here. In the usual rule of reason case, to establish a violation of § 1, plaintiffs must prove:

(1) that the defendants contracted, combined or conspired among each other; (2) that the combination or conspiracy produced adverse, anti-competitive effects within the relevant product and geographic markets; (3) that the objects of and the conduct pursuant to that contract or conspiracy were illegal; and (4) that the plaintiffs were injured as a proximate result of that conspiracy.

Tunis Bros. Co., Inc. v. Ford Motor Co., 763 F.2d 1482, 1489 (3d Cir.1985) (citations omitted), vacated on other grounds, Ford Motor Co. v. Tunis Brothers Co. Inc., 475 U.S. 1105, 106 S. Ct. 1509, 89 L. Ed. 2d 909 (1986) . Here, because per se analysis applies, prongs two and three are conclusively presumed satisfied and need not be addressed. Accordingly, to prevail on summary judgment, Rossi need only show the existence of a genuine issue of material fact regarding concerted action and proximate causation. We will address these in turn.

1. Section 1 of the Sherman Antitrust Act--Proving the Conspiracy

The presence of concerted action or an agreement is an essential element of a § 1 claim. See Copperweld Corp. v. Independence Tube Corp., 467 U.S. 752, 771, 104 S. Ct. 2731, 81 L. Ed. 2d 628 (1984) ("[U]nity of purpose or a common design and understanding, or a meeting of the minds in an unlawful arrangement" must exist to trigger section 1 liability.) (internal quotes omitted); Alvord-Polk, Inc. v. F. Schumacher & Co., 37 F.3d 996, 999-1000 (1994) (noting that the existence of concerted action is one of the important distinguishing features between a § 1 claim of conspiracy and a § 2 claim of monopolization). Unilateral activity, no matter what its motivation, cannot give rise to a § 1 violation, see Sweeney, 637 F.2d at 110-11, because a manufacturer "has the right to deal, or refuse to deal, with whomever it likes, as long as it does so independently." Monsanto Co. v. Spray-Rite Serv. Corp., 465 U.S. 752, 761, 104 S. Ct. 1464, 79 L. Ed. 2d 775 (1984). A plaintiff may utilize either direct or circumstantial evidence in order to make out the element of concerted action. While direct evidence, the proverbial "smoking-gun," is generally the most compelling means by which a plaintiff can make out his or her claim, it is also frequently difficult for antitrust plaintiffs to come by. Thus, plaintiffs have been permitted to rely solely on circumstantial evidence (and the reasonable inferences that may be drawn therefrom) to prove a conspiracy. See Alvord-Polk, 37 F.3d at 1000 (citing Theatre Enterprises, Inc. v. Paramount Film Distributing Corp., 346 U.S. 537, 74 S. Ct. 257, 98 L. Ed. 273 (1954); Sweeney, 637 F.2d at 111).

While the traditional summary judgment standard applies with equal force in antitrust cases,9 when the plaintiff relies solely on circumstantial evidence to prove concerted action, this analysis is modified in accordance with the leading antitrust cases dealing with this subject, Monsanto and Matsushita Elec. Indus. Co., Ltd. v. Zenith Radio Corp., 475 U.S. 574, 587, 106 S. Ct. 1348, 89 L. Ed. 2d 538 (1986), and their progeny. In Matsushita, the Supreme Court explained the limitation courts must apply to permissible inferences when deciding a summary judgment motion in an antitrust conspiracy case: "[C]onduct as consistent with permissible competition as with illegal conspiracy does not, standing alone, support an inference of antitrust conspiracy." Matsushita, 475 U.S. at 588, 106 S. Ct. 1348 (citing Monsanto, 465 U.S. at 764, 104 S. Ct. 1464). Rather, to survive a motion for summary judgment, "a plaintiff seeking damages for a violation of § 1 must present evidence 'that tends to exclude the possibility' that the alleged conspirators acted independently," id., "direct or circumstantial evidence that reasonably tends to prove that [the alleged conspirators] 'had a conscious commitment to a common scheme designed to achieve an unlawful objective.' " Monsanto, 465 U.S. at 764, 104 S. Ct. 1464 (quoting Sweeney, 637 F.2d at 111).

The Supreme Court's concerns about permitting the inference of a conspiracy from ambiguous circumstantial evidence in the antitrust context stem from its conclusion that mistakes by an overzealous judiciary would be "especially costly ... chill[ing] the very conduct the antitrust laws are designed to protect." Matsushita, 475 U.S. at 594, 106 S. Ct. 1348; Monsanto, 465 U.S. at 763, 104 S. Ct. 1464; Big Apple BMW, 974 F.2d at 1363 ("Care must be taken to ensure that inferences of unlawful activity drawn from ambiguous evidence do not infringe upon defendant's freedom, so long as it acts independently, to refuse to deal.") (citing United States v. Colgate & Co., 250 U.S. 300, 39 S. Ct. 465, 63 L. Ed. 992 (1919)). For this reason, the plausibility of an antitrust plaintiff's claim is important. "[I]f the factual context renders [the plaintiff's] claim implausible--if the claim is one that simply makes no economic sense--[a plaintiff] must come forward with more persuasive evidence to support [its] claim than would otherwise be necessary." Matsushita, 475 U.S. at 587, 106 S. Ct. 1348 (citations omitted). Relatedly, in evaluating whether a genuine issue for trial exists, the antitrust defendants' economic motive is highly relevant. "[I]f[the defendants] had no rational economic motive to conspire, and if their conduct is consistent with other, equally plausible explanations, the conduct does not give rise to an inference of conspiracy." Id. at 596, 106 S. Ct. 1348. Moreover, even with a plausible motive to conspire, ambiguous conduct will not create a triable issue of fact with respect to the existence of a conspiracy. See id. at 597 n. 21, 106 S. Ct. 1348.

Under our jurisprudence, the Matsushita standard only applies when the plaintiff has failed to put forth direct evidence of conspiracy. See Petruzzi's IGA Supermarkets, Inc. v. Darling-Delaware Co., Inc., 998 F.2d 1224, 1233 (3d Cir.1993). Thus, in direct evidence cases, the plaintiff need not adduce circumstantial evidence " 'that tends to exclude the possibility' that the alleged conspirators acted independently," Matsushita, 475 U.S. at 588, 106 S. Ct. 1348, and there need not be an inquiry into the plausibility of the defendants' claim or the rationality of defendants' economic motives. See id. at 596-97, 106 S. Ct. 1348. This is because when the plaintiff has put forth direct evidence of conspiracy, the fact finder is not required to make inferences to establish facts, and therefore the Supreme Court's concerns over the reasonableness of inferences in antitrust cases evaporate. See Petruzzi's, 998 F.2d at 1233.

Additionally, our jurisprudence does not require the summary judgment opponent to " 'match, item for item, each piece of evidence proffered by the movant,' " but rather he or she must only exceed the " 'mere scintilla' " standard. See Petruzzi's, 998 F.2d at 1230 (quoting Big Apple BMW, 974 F.2d at 1363). Accordingly, when examining the sufficiency of what the plaintiff has adduced, we are not to "tightly compartmentalize the evidence," but rather we must evaluate it as a whole to see if it supports an inference of concerted action. See id. at 1230.

In sum, Matsushita does not introduce a special burden on antitrust plaintiffs opposing summary judgment; it "demands only that the nonmoving party's inferences be reasonable in order to reach the jury, a requirement that was not invented, but merely articulated, in that decision. If the plaintiffs theory is economically senseless, no reasonable jury could find in its favor, and summary judgment should be granted." Eastman Kodak, 504 U.S. at 468-69, 112 S. Ct. 2072 (footnote omitted). Conversely, Matsushita does not mean that antitrust defendants are entitled to summary judgment merely by showing that there is a plausible explanation for their conduct; rather "the focus must remain on the evidence proffered by the plaintiff and whether that evidence 'tends to exclude the possibility that [the defendants] were acting independently.' " Petruzzi's, 998 F.2d at 1232 (quoting Monsanto, 465 U.S. at 764, 104 S. Ct. 1464). Thus, where the nonmoving party has put forth evidence that provides an inference of concerted action, the moving party "bears the burden of proving that drawing the inference of unlawful behavior is unreasonable." Id. at 1230.

Finally, while ambiguous conduct cannot create a triable issue of fact, when "the alleged conduct is 'facially anticompetitive and exactly the harm the antitrust laws aim to prevent,' no special care need be taken in assigning inferences to circumstantial evidence." Alvord-Polk, 37 F.3d at 1001 (quoting Eastman Kodak, 504 U.S. at 478, 112 S. Ct. 2072).

With these standards in mind, we will address the evidence adduced by Rossi in support of his theory of conspiracy. Cognizant of our obligation to view the evidence as a whole and to resist the temptation to compartmentalize it, see Petruzzi's, 998 F.2d at 1230, we will nonetheless consider Rossi's allegations, defendant by defendant, to provide a logical structure to our analysis. We note in this regard that this court has been relatively hospitable to the efforts of plaintiffs to prove concerted action. See Alvord-Polk, 37 F.3d at 1010, 1013; Petruzzi's, 998 F.2d at 1247; Big Apple BMW, 974 F.2d at 1380, 1383; Arnold Pontiac-GMC, Inc. v. Budd Baer, Inc., 826 F.2d 1335, 1338-39 (3d Cir.1987); Arnold Pontiac-GMC, Inc. v. General Motors Corp., 786 F.2d 564, 572-75 (3d Cir.1986); Tunis Bros., 763 F.2d at 1489, 1502.

a. Standard (Robert Higginson, William Higginson, Joseph Licciardello) and Arzee (Al Roth and Cary Roth)

We begin with Rossi's horizontal competitors, Standard and Arzee, against whom Rossi has the strongest evidence of motive to keep a price-cutting competitor with close ties to many customers from entering the market. Standard's and Arzee's (as well as the other defendants') first line of defense to Rossi's charges is that the conspiracy he alleges is implausible, and therefore under Matsushita, permitting an inference of antitrust conspiracy would have the effect of "chill[ing] the very conduct the antitrust laws are designed to protect." 475 U.S. at 594, 106 S. Ct. 1348. According to the defendants, there was no rational economic reason for them to conspire, and thus they had no plausible motive to conspire to boycott Rossi.

They base their implausibility claim on the fact that the market was extremely price competitive and consisted of upwards of three dozen competing distributors. Under these conditions, defendants argue that they could not have charged above-market prices and stayed in business, and thus that they had nothing to fear from a price-cutter like Rossi. Moreover, they submit that there would be little to gain by excluding one more distributor from the market when there were at least three dozen firms in the market already. In defendants' view, any conspiracy to stabilize the market and reap enhanced profits would be doomed to failure (and is therefore presumably implausible) because, to succeed, it would have required an enormously complex and far-reaching undertaking, involving upwards of sixty participants (each selling different quantities of comparable, competing products) to stabilize prices at supra-competitive levels. Defendants maintain that, because there was virtually no likelihood that three (Standard, Arzee, and Allied) out of the almost forty competing distributors, and one or two (GAF and possibly Wood Fiber) out of thirty manufacturers could have sustained such a conspiracy, they had no rational motive to conspire, and the conspiracy is thus implausible.

The defendants compare this to the situation in Matsushita. There, the defendants were alleged to have entered into a twenty-plus-year conspiracy to fix prices in the electronics market below the market level in the hopes of establishing a monopoly and extracting monopoly profits in the undetermined future. See Matsushita, 475 U.S. at 588-90, 106 S. Ct. 1348. The Court viewed this predatory pricing scheme as implausible because it would have required multiple defendants to endure tremendous up-front losses for the foreseeable future in the hopes that they could, at some point, recover these losses and make even greater profits once they had driven their competitors from the market and established a monopoly. See id. at 589-90, 106 S. Ct. 1348. The Court, examining the electronics market as well as the length and ongoing failure of the alleged conspiracy, concluded that there was no evidence that the defendants could ever recoup such losses, see id. at 594-95, 106 S. Ct. 1348, and therefore, that the defendants had no motive to engage in the conspiracy. See id. at 595, 106 S. Ct. 1348.

Standard's and Arzee's reliance on Matsushita in this case is misplaced for several reasons. As a threshold matter, Matsushita does not apply when there is direct evidence of conspiracy. See Petruzzi's, 998 F.2d at 1233. Here, Rossi has adduced direct evidence of concerted action between defendants Standard and Arzee in the form of a threat Rossi received in December of 1988. Joseph Licciardello, who had by that time left his job at GAF and was working in Rossi's old job as manager of the Standard branch at Cedar Knolls, told Rossi that Standard and Arzee would do whatever it took to put him out of business if he persisted with his plans to found Rossi Florence. In his deposition, Rossi testified:

Q: Mr. Rossi, tell me specifically what anyone from Standard did to prevent Rossi Florence from going into business.

* * *

A: I guess it started when Joe Licciardello came over and threatened me that if I went into business that he and Arzee Supply would do anything they could, stop supplies, cut the prices, whatever they had to do they were going to do to keep me out of business. That's the way he put it.11

Licciardello's threat, viewed in a light most favorable to Rossi, indicates that two of his competitors had discussed and agreed to act jointly to prevent Rossi from competing with them in the roofing and siding business in northern New Jersey. Moreover, Licciardello's statement even details how the two companies planned to do it; they agreed to "stop supplies" anyway they could. Thus, we conclude that the Matsushita implausible conspiracy argument is not relevant to the allegations of conspiracy with respect to Standard and Arzee. However, even if, as in the case of GAF, there was no direct evidence of concerted action, the conspiracy Rossi alleges is not implausible. Indeed, as we will discuss below, with respect to Standard, Arzee, and GAF, the conspiracy makes perfect sense. See infra § II.B.2.b(1).

The direct evidence discussed above is enough to take the case against Standard and Arzee beyond the constraints of Matsushita (and thus permits us to avoid the questions whether the circumstantial evidence tends to exclude the possibility of independent action, whether the plaintiff's claim is plausible, and whether the defendants' economic motives were rational). See supra at § II.B.1. However, it is not enough by itself to satisfy Rossi's burden in opposing summary judgment. On the other hand, Rossi has adduced a significant collection of other evidence, circumstantial in nature, in support of his position. We turn to that evidence now.

First, Rossi has adduced evidence of two meetings between Standard and Arzee employees which, when taken together, support the inference of a joint motive by the two defendants to unlawfully stabilize roofing prices in northern New Jersey. This motive is consistent with the motive behind the defendants' alleged boycott of Rossi Florence and Rossi Roofing--that Standard and Arzee wanted to eliminate an uncooperative competitor who threatened to undercut their prices and destabilize the market. Rossi testified that sometime in 1986 or 1987, while he was still working for Standard (he was fired in September 1989), his boss at that time and chairman of Standard, Robert Higginson, directed him to attend a lunch with Al and Cary Roth of Arzee. According to Rossi, Robert Higginson told him that this lunch had been set up so that the two competitors could "cooperate" and share price information. Robert Higginson also told Rossi that Standard's other competitors had pricing agreements and that they were the only ones who were not participating. At the lunch, Al Roth proposed to Rossi a price-fixing scheme whereby Arzee and Standard would fix prices and divide up their large customers and jobs. Al Roth further explained to Rossi that he had maintained a similar arrangement with Allied concerning Certainteed products. Rossi rejected Al Roth's overtures, and Standard and Arzee did not, at that time, enter into an agreement to set prices.

The second Standard-Arzee meeting at which prices were discussed took place over the telephone in February of 1990. It involved a conversation between Licciardello, the manager at that time of Standard's Cedar Knolls branch, and Cary Roth, the manager of one of Arzee's local branches, regarding the price of GAF vinyl siding. Patrick Mulcahy, a former employee of Standard who overheard the conversation, recalled that Licciardello said to Cary Roth: "We really got to run this like a business and we all have to make a profit here. And we've got to keep certain price levels in order to do this."12 This statement is remarkably similar to other statements that we have found probative of an agreement between competitors. See, e.g., Petruzzi's, 998 F.2d at 1236 ("[W]hy don't you put your prices in line and make money on what you have?").

Neither of these discussions took place during the period of the alleged conspiracy to boycott and exclude Rossi from the market; one took place before, and one after. Yet we reject Standard's and Arzee's contention that they are irrelevant to our decision. The two pieces of evidence, especially taken together, are probative of Standard's and Arzee's motive. Evidence that Standard's and Arzee's principals had actively considered fixing prices and allocating customers in 1986-87, and again in 1990, is sufficient to permit the inference that Standard and Arzee may have had a long-standing intent to stabilize prices in the roofing distribution business in northern New Jersey. See Big Apple BMW, 974 F.2d at 1360-61 (reviewing evidence outside of the statute of limitations and thus not part of the alleged conspiracy which nevertheless "demonstrat[ed] a pattern of conduct"); see also Andresen v. Maryland, 427 U.S. 463, 483-84, 96 S. Ct. 2737, 49 L. Ed. 2d 627 (1976) (proof of similar acts is admissible to show intent or the absence of mistake); Keyes v. School District No. 1, 413 U.S. 189, 207-08, 93 S. Ct. 2686, 37 L. Ed. 2d 548 (1973) (citing the well-settled evidentiary principle that " 'the prior doing of other similar acts, whether clearly a part of a scheme or not, is useful as reducing the possibility that the act in question was done with innocent intent.' ") (quoting 2 J. Wigmore, Evidence 200 (3d ed.1940)). Because Rossi was known to the defendants as a price-cutter and potent competitor who had refused to collude on prices in the past, this circumstantial evidence tends to link Standard's and Arzee's motives with their other actions in support of the boycott, which are detailed below.

The record is also replete with examples of high pressure recruitment, monitoring, and enforcement tactics undertaken by Standard and Arzee in furtherance of their efforts to prevent Rossi from purchasing roofing materials, particularly GAF product. There is evidence that Standard and Arzee put pressure on virtually everyone, including manufacturers, distributors, and even Rossi's prospective business partner, Droesch, to convince them not to do business with Rossi. In December 1988, for example, Al Roth called Droesch, who had agreed to establish Rossi Florence and go into business with Rossi, and told him that he was not happy about Rossi competing against Arzee and that if Droesch proceeded with his plans to establish Rossi Florence with Rossi, Roth would open up an Arzee location on Long Island near Droesch's Florence business which was located there. Also in late 1988 and early 1989, representatives of several manufacturers told Rossi that they were being pressured not to deal with him or sell to Rossi Florence. Specifically, Rossi testified that representatives from Gold Bond, Wood Fiber, Bird Corporation, Homosote, Hi-Finn, Genstar, Vipco, and Hastings Aluminum, told him that they had been threatened by representatives of Standard. Similarly, representatives of Nailite and Certainteed claimed that they had been threatened by Arzee.13

There was evidence that after Rossi incorporated Rossi Roofing in early 1989, Standard's and Arzee's pressure on manufacturers and distributors continued. Joe Mullenhour of Bird Corporation told Rossi that Licciardello of Standard had threatened to drop Bird's vinyl siding if Bird Corporation sold to Rossi Roofing. Bill Higginson of Standard also spoke to Raymond Six of Gold Bond and told him that he was "disappointed" that Gold Bond had agreed to sell to Rossi Roofing. Six cut off the conversation because he was concerned by the antitrust implications of Bill Higginson's overtures. More specifically, Six told Higginson that he would not let the conversation go further because:

Gold Bond had been in an anti-trust suit back in the 70's on gypsum. Every Gold Bond manager--well, I'll say every Gold Bond employee had been schooled, I'll say, from 1975 on, anyway, on what Robinson-Patman is, what Sherman anti-trust was. So the conversation wasn't going to go any further than what my statement to him was.

When Rossi asked Jim Hines of Hi-Finn to supply Rossi Roofing with the "Atlas" insulation line, he arranged for Rossi to buy the product indirectly through a middleman at a higher price. When Hines later visited Standard on a sales call, Licciardello told him, "You know why I can't do business with you." Hines replied that "if it has anything to do with the truck of Atlas insulation that Joe Rossi has in stock, that was purchased through another distributor, not directly through Atlas." Licciardello referred Hines to Bob Schaab, Standard's Controller, who told Hines to "[d]o what you want to." Based upon his experience with Schaab and his dealings with Standard, Hines testified that he concluded that conversation with "the feeling that his implication may have been that, if I sold to Joe [Rossi], he definitely wouldn't buy from me." Finally, Hines testified that his business with Standard fell off right around the time that Rossi purchased the Atlas insulation from the middleman recommended by Hines. On this evidence, a fact finder could reasonably draw the inference that Licciardello had threatened Hines to ensure Hi-Finn's cooperation in the boycott of Rossi, and that, when Hines rebuffed him, Standard punished Hines and Atlas by cutting off future purchases.

Similarly, Rick Fiore, an employee of roofing manufacturer Certainteed, told Rossi that Cary Roth of Arzee had pressured him and threatened to sue Certainteed if it sold to Rossi Roofing. Robert Qualik of Nailite informed Rossi that Arzee had told Nailite not to sell to Rossi Roofing and that "[Arzee] had blocked [Rossi Roofing] from getting product on a particular job right around the corner from us." Also, Karl Loser of Wood Fiber told Rossi that he was receiving a lot of pressure from Standard not to sell Structodek FS, a Wood Fiber product, to Rossi Roofing.

In an effort to circumvent these supply problems arising from his efforts to buy directly from manufacturers, Rossi attempted to purchase product through other distributors, even though this would cost more. For example, Rossi was able to convince Passaic Metals, a roofing and siding distributor in northern New Jersey, to sell him some GAF product. In response, Bill Higginson of Standard called his competitor, Frank Gurtman, the president of Passaic Metals, and threatened to open a branch near Passaic Metals and take away all of his customers if Gurtman continued to sell to Rossi.

There is also evidence that Standard and Arzee went to great lengths to monitor Rossi Roofing. The record indicates that Licciardello ordered Keith Cogley and Jorge Esteves to report to him the comings and goings of all roofing materials at Rossi Roofing. All three closely watched Rossi's premises on a daily basis to determine what kinds of products Rossi was able to purchase and from where they might be coming. Cary Roth and Ed Jacobitz of Arzee also frequently monitored Rossi Roofing by sitting in their cars in a cul-de-sac adjacent to Rossi's premises.

In addition, there is evidence that Standard even reported back to GAF when its employees saw GAF product on Rossi's premises to assist GAF in enforcing the boycott. Former GAF district manager Licciardello, then working for Standard, admitted that after seeing GAF product on Rossi's premises, he called Bob Gessner of GAF to confirm that GAF was still not selling to Rossi. On another occasion, when a load of GAF was sitting out in front of Rossi Roofing, Gessner said to Licciardello, "I thought we weren't selling him," to which Licciardello responded "we're not."

When Standard's Cogley saw a load of GAF product at Rossi Roofing, Licciardello called GAF to find out how Rossi had procured the product. Someone at GAF told Licciardello that the load was not for Rossi Roofing, but that it was being transported on a Jentar truck, and was simply stopping overnight at 8 East Frederick Place, where both Jentar Trucking and Rossi Roofing had offices. Later, after Licciardello learned that Rossi Roofing had purchased GAF product from Servistar through his Far Hills account, see infra § II.B.2.c, Licciardello told Standard employee Esteves that " 'That's the last time we're going to be seeing any GAF across the street.' They got the--they were getting the loads through [Far Hills], which is [Servistar]. That's how Joe Rossi was getting GAF and he's [Licciardello's] going to put an end to that. 'Never going to see another GAF load across the street.' "

While this monitoring and reporting activity would not in isolation be probative of a conspiracy, in the context of the pressure and enforcement tactics described above, the direct evidence that Standard and Arzee had talked about and agreed to boycott Rossi Florence and Rossi Roofing, and the circumstantial evidence of motive, certain inferences can be drawn from this evidence. To enforce a boycott, Standard and Arzee would need to monitor carefully the supplies Rossi was able to procure, communicate to cooperating manufacturers any evidence that Rossi had been able to circumvent the boycott, and bring pressure on any non-cooperating manufacturers or distributors that refused to participate in the conspiracy. Here, Rossi has adduced evidence of exclusive monitoring by both Standard and Arzee, and evidence that Licciardello could "put an end" to Rossi receiving GAF product. Viewed in conjunction with the evidence that Standard and Arzee pressured many manufacturers and distributors, this monitoring and reporting activity also supports an inference that Rossi's two primary competitors were jointly attempting to establish a market-wide boycott of Rossi Roofing.

We emphasize that we would not consider the evidence that Standard and Arzee aggressively monitored Rossi Roofing (and even reported the substance of those observations to GAF), without more, sufficient to satisfy Rossi's burden in opposing summary judgment. However, in conjunction with all of the other pieces of circumstantial evidence Rossi has adduced, we believe that this monitoring and reporting activity represents an important thread to be considered in the complicated tapestry of conspiracy that Rossi weaves.

Looking at all of the evidence Rossi has assembled against Standard and Arzee, we conclude that he has satisfied his burden in opposing summary judgment on the concerted action prong. First, Rossi has developed direct evidence that Standard and Arzee had, both before and after Rossi Roofing existed, attempted to conspire to fix prices, allocate customers, and otherwise stabilize the roofing and siding distribution market in northern New Jersey. He has also shown that both defendants knew him to be a price-cutting competitor who had frustrated their unlawful purposes by refusing to cooperate with them. These two facts provide strong evidence of the defendants' motive to conspire against Rossi. Desiring to raise prices above their competitive levels in a highly competitive market, an inference is supported that Standard and Arzee were concerned that they could not succeed without Rossi's cooperation, and that they therefore decided to prevent him from competing against them.

Next, Rossi points us to direct evidence of the boycott, namely Licciardello's threat on behalf of Standard and Arzee to cut off his supplies and put him out of business. Finally, Rossi has developed considerable evidence of Standard's and Arzee's elaborate efforts to enforce the boycott. Rossi has produced testimony that many manufacturers and distributors were pressured and/or threatened not to do business with Rossi Florence and Rossi Roofing. He has also adduced testimony that Standard and Arzee had an elaborate monitoring system in place, one which even included reporting back to GAF to help enforce the boycott.

To be sure, this evidence is far from conclusive. It could be found at trial that Standard, Arzee, and GAF were all acting independently of one another in parallel efforts to do Rossi in. However, given the comprehensive nature of the evidence covering all elements of the group boycott Rossi alleges, we must reverse the district court's order granting summary judgment in favor of Standard, Arzee, Robert Higginson, William Higginson, the Roths, and Licciardello.

b. GAF

We also believe that Rossi has adduced sufficient evidence that GAF acted in concert with Standard and Arzee to survive its motion for summary judgment and will reverse the district court with respect to GAF as well.

(1) Matsushita Implausibility

GAF's first defense, like Standard's and Arzee's, is that the conspiracy alleged by Rossi is implausible under Matsushita. Because Licciardello's statement that Standard and Arzee intended to establish a boycott of Rossi Roofing is insufficient by itself to hold in GAF, and we can find no (other) direct evidence of GAF's participation in the alleged conspiracy in the record, we must analyze, under the Matsushita standard, the plausibility of the conspiracy that Rossi alleges. See supra § II.B.2.a. In contrast with that case, we find that the theory Rossi advances with respect to GAF's motivations and participation in the conspiracy is not economically implausible.

First, Rossi's claim does not, as defendants allege, require the cooperation of dozens of distributors and manufacturers (each selling different quantities of comparable competing products) in the northern New Jersey marketplace to succeed (i.e. for distributors Standard, Arzee, and Allied to be able to charge supra-competitive prices). Rather, it is primarily focused on the actions of three distributors, Standard, Arzee, and Allied, and one manufacturer, GAF. Despite the fact that this case arises against the backdrop of the highly competitive, price-sensitive roofing and siding industry in northern New Jersey in 1989 and 1990, Rossi advances a plausible theory of how these defendants could have unlawfully conspired to fix prices and therefore why they would want to boycott Rossi. Moreover, even if Standard and Arzee were not conspiring to keep prices artificially inflated by pocketing the secret rebates that their competitors were not receiving, both still had a plausible motive to keep Rossi, an avowed and experienced price-cutter and acknowledged potent competitor with a reputation among their customers for excellent service, from opening up a competing distributorship next door.

In order to comprehend the plausibility of the conspiracy Rossi alleges, it is necessary to understand GAF's position in the market and the importance of GAF product. In 1990, GAF was indisputably one of the largest and most important manufacturers of roofing supplies in the northern New Jersey market, with an estimated 38% share of the entire residential roofing shingle market in New Jersey and an estimated 71% share of the residential roofing laminate shingle market in New Jersey. GAF not only supplied a large percentage of the overall market, but it also was Standard's single largest supplier during the time that Rossi was a manager there. As such, Rossi was extremely familiar with GAF, and a large percentage of his customers, many of whom followed him from Standard to Rossi Roofing, had a strong preference for GAF product. Indeed, there is substantial testimony in the record from many sources supporting Rossi's contention that GAF product was critical to both Rossi Florence's and Rossi Roofing's success in the market.

For example, Sean Coffey, one of the five largest residential roofers in northern New Jersey, testified that he used GAF product in 1989 and 1990 almost exclusively and would not buy from any roofing distributor that did not have access to it. Similarly, Francis Doherty, proprietor of another large roofing business in northern New Jersey, testified that "99 percent" of his strip shingle purchases had been GAF product. John Feher, another roofer who attempted to purchase GAF product from Rossi Roofing, testified that GAF was very popular with everyone, including contractors and homeowners, because "it's easy to get and guarantees [sic] and everything is good on it." Thomas Harnett, an executive at Bird Corporation, testified that GAF "dominated all levels of roofing in New Jersey," and that it was a "highly desirable product."

Likewise, Albert Logan, a former Celotex employee, stated that GAF had "dominate[d] the market for years," representing at least fifty percent of every distributor's inventory. John Mulcahy, a former Standard employee, also testified that GAF was "dominant and had ... [its] product[s] so well-established in the area." Because of this, Mulcahy stated that any distributor denied access to GAF product would have difficulty competing in the residential shingle market. Id. When asked to describe the magnitude of the adverse impact of trying to compete without GAF product, Mulcahy stated, "It would be like a beer distributor not having Budweiser."

Finally, another former employee at Standard, Michael Hydro, testified that GAF comprised eighty percent of his sales while he worked there and at least five of Standard's customers purchased exclusively GAF product. He also explained that in 1989 and 1990, a large number of townhouse projects were already "spec'd" with GAF product, which made it impossible for the roofers to switch product lines mid-stream. Thus, anyone who could not supply GAF product was effectively barred from bidding for these jobs. On the basis of all of this evidence, we believe that Rossi has demonstrated that a genuine issue of material fact exists as to whether GAF product was special, and necessary for a distributor like Rossi to successfully compete in northern New Jersey.

Against this background on the roofing market in general and GAF's place in the market in particular, we move to the evidence Rossi adduced that GAF used secret rebates with several of its biggest distributors in northern New Jersey, including Standard, Arzee, and Allied, for that is critical to understanding the motivations of Rossi's horizontal competitors. Pursuant to this scheme, GAF provided these distributors off-invoice, non-volume discounts on their purchases. These "rebates," assuming they were only offered to a few favored distributors as Rossi contends, allowed those distributors to sell GAF product at or below the prevailing market price (as set by the distributors who did not receive the discounts) while secretly conspiring to pocket the difference. In GAF district sales manager Bud Krusa's words, "the less [sic] people [who] knew about it [the discounts], the less chance you [the smaller distributors] have of getting it[and] dropping the entire market price." The most favorable inference we can draw for Rossi from Krusa's statement is that if these highly secret rebates became widely known, the smaller distributors who were not receiving rebates would have put pressure on GAF to receive equal treatment, and that this shakeup of the market could ultimately destabilize prices, lead to a price war, and "drop[ ] the entire market price" for GAF product.

By adducing evidence of the GAF rebate scheme and the importance of GAF and GAF product, Rossi transforms what might otherwise have been a very difficult (and implausible) conspiracy into a realistic opportunity for a few cooperating competitors to fix prices and earn substantial profits while still operating within what appears to be a competitive marketplace. Cf. Brooke Group Ltd. v. Brown & Williamson Tobacco Corp., 509 U.S. 209, 239, 113 S. Ct. 2578, 125 L. Ed. 2d 168 (1993) (holding that a conspiracy to fix supra-competitive prices in a market with many variables was implausible because of the complexity required to monitor and enforce it) (citations omitted).

We find this case, as it relates to GAF, Standard, and Arzee, fundamentally unlike Matsushita. There, the critical problem with the conspiracy as alleged was that the conspirators had been losing large sums of money over a period of twenty plus years by undercutting the market in the hope of building market share and eventually establishing a monopoly. Not only did the Court find it difficult to distinguish the allegedly predatory pricing strategy from actual price competition, but given the extremely low chance that the scheme would succeed, the Court concluded that the defendants, if they operated in a rational manner, had no motive to engage in the conduct with which they were charged. In contrast, it is not difficult to divine the likely motive of the three distributors, Standard, Arzee, and Allied, in boycotting Rossi. As Rossi's horizontal competitors, they wanted to rid the market of a price-cutting competitor with a reputation for excellent service and reliability who had refused to cooperate in their price-fixing schemes in the past. Moreover, Rossi is aided in asking us to permit the fact finder to draw this inference by the strong likelihood that the boycott would actually succeed (as evidenced by the results).

Even if all of this is true, submits GAF, it still does not explain why it would make sense for GAF to join the conspiracy. We agree that GAF's motive, as the manufacturer-supplier, is less obvious than Standard's or Arzee's, but ultimately we find it no less compelling. This is because Rossi has adduced evidence that Standard, Arzee, and Allied possessed substantial economic leverage over GAF. Together, they purchased $10.7 million of the $24.1 million of GAF product sold in New Jersey in 1989, or 44.5% of GAF's total northern New Jersey sales. These distributors were not happy about the prospects of Rossi entering the market and competing with them, and they made their views known to GAF. Complaints and threats from three of GAF's largest customers in New Jersey are sufficient to establish a rational motive for GAF to engage in the concerted conduct that Rossi alleges. For these reasons, we do not accept GAF's submission that Rossi's conspiracy theory, and the economic motivations behind it, are inherently implausible.

(2) Circumstantial Evidence Against GAF

We turn next to the circumstantial evidence that supports Rossi's allegations that GAF joined with Standard and Arzee (and potentially others) to enforce a market-wide boycott of first Rossi Florence and later Rossi Roofing, The evidence comes in several forms. First, as we will detail, Rossi has adduced evidence that GAF received numerous complaints about Rossi's pricing practices while he was at Standard and responded to them by asking Rossi to raise his resale prices on GAF product. While these complaints antedate Rossi entering the marketplace, they are useful background information to establish motive and practice. See Big Apple BMW, 974 F.2d at 1360-61.

Second, GAF participated in the group boycott against Rossi through monitoring and enforcement activities and the implementation of an unprecedented anti-transshipment policy. Third, there is evidence that GAF singled out Rossi and acted contrary to its own corporate policy in refusing to deal with him (an important factor under Monsanto and Matsushita ), in that GAF employees testified that the company had an "open distribution" policy under which they sold to all comers, yet GAF refused to sell to Rossi and went to considerable lengths to see that he was not able to secure GAF product from other sources. Finally, Rossi has also adduced evidence that two of GAF's explanations why it refused to deal with him--that it had adequate distribution in New Jersey and product shortage--were pretextual.

(a) Distributors' Complaints and GAF's Response

While Rossi worked at Standard, the company received, as did Arzee and Allied, the off-invoice, non-volume rebates discussed supra. Rossi used these rebates to reduce the prices he charged to his customers in an effort to increase sales volume; he did not, as his competitors did, retain the rebates to increase gross profits. This aggressive price-cutting strategy understandably angered Standard's competitors, and several of them complained to GAF about Rossi's behavior. Krusa and Licciardello, both then working as GAF district sales managers in the New Jersey region, frequently called Rossi at Standard and passed along the complaints of Arzee, Allied, Passaic Metals and others about Rossi's pricing. Krusa and Licciardello also called Bob Schaab, the Controller of Standard, to complain that Rossi was passing on the discounts given by GAF to Standard to his customers.

Although GAF did not have suggested resale prices, Krusa and Licciardello told Rossi to raise his resale prices for GAF product. Schaab, relaying GAF's messages, also asked Rossi to refrain from passing the GAF rebates to Standard's customers. Rossi refused, and vowed to price as he saw fit. This evidence suggests several things. First, it reaffirms the motives of Rossi's horizontal competitors, Arzee and to a lesser extent Standard. Second, it shows that a group of distributors (even a group that did not include Standard) could wield economic leverage over GAF and influence its interactions with recalcitrant distributors. Third, it suggests that GAF's course of conduct was to curry favor with its larger distributors by doing what it could to assist them in stabilizing the market and keeping price levels up.

We agree with GAF that evidence that it succumbed to pressure from distributors is not sufficient, by itself, to survive summary judgment, since the evidence of complaints and threats GAF received from Standard and Arzee is not enough in isolation to prove concerted action. See Monsanto, 465 U.S. at 763-64, 104 S. Ct. 1464 ("[p]ermitting an agreement to be inferred merely from the existence of complaints, or even from the fact that termination came about 'in response to' complaints, could deter or penalize perfectly legitimate conduct."); Sweeney, 637 F.2d at 111. However, we do not rely solely on these complaints. Rather, there is a substantial amount of additional evidence to support a finding of an unlawful conspiracy. In this circumstance, we are permitted to consider the evidence of distributor complaints. See Monsanto, 465 U.S. at 764 n. 8, 104 S. Ct. 1464 ("We do not suggest that evidence of complaints has no probative value at all, but only that the burden remains on the antitrust plaintiff to introduce additional evidence sufficient to support a finding of an unlawful contract, combination, or conspiracy.").

(b) Actions in Contravention of GAF Corporate Policy

GAF's boycott against Rossi appears to be contrary to its own corporate policy, particularly in light of the evidence adduced of GAF's draconian enforcement and anti-transshipment activities. There is testimony in the record that GAF had an open distribution system. Peter Bacchione, GAF's director of marketing and sales and Krusa's superior in 1989, testified that GAF never had a closed distribution network and never rejected a potential distributor because the local market was saturated. Bacchione testified:

Q: Do you recall in 1989 whether GAF, with respect to the roofing products that you had responsibility for, had any particular objectives with respect to increasing, decreasing, or otherwise, its distribution channel.

A: ... We always looked to increase our share of business with any distributor.

Q: Did GAF have any exclusive distributors for roofing products while you were national sales director?

A: No.

* * *

Q: Wasn't GAF's philosophy to have an open distribution network?

* * *

A: Maybe it was--maybe it was a philosophy. A practice. Whether it was a philosophy that was up on a wall some place, I don't recall that.

Q: Was it the practice?

A: Generally, we sold on an open basis. There were no exclusivities.14

This testimony directly contradicts GAF's litigation position as stated by Krusa, who has maintained since 1989 that GAF refused to supply Rossi because it had "adequate distribution."15 Krusa is also contradicted by Lorraine Campbell, Ruth Rogers, Mary Lou Sperr and Bob Tafaro, all of whom worked for Krusa, and all of whom testified that Krusa never told them that GAF had adequate distribution in New Jersey. Finally, Rossi submits that Krusa is contradicted by the fact that GAF supplied 34 out of the 39 distributors in northern New Jersey, and only refused to sell to three distributors including Rossi Roofing. On summary judgment, of course, we need not resolve this dispute, but rather grant Rossi all favorable inferences.

(c) Monitoring and Enforcement Activities

GAF, through Krusa and Licciardello, took still more steps to ensure that Rossi did not get any GAF product. In January 1989, when Droesch told Krusa that he planned to buy GAF product through his Florence Corporation in Long Island and resell it to Rossi Florence, Krusa told Droesch that "he would not allow that and he would not sell me [sic] in Long Island if I did that." GAF also warned other distributors not to resell its products to Rossi, and there is evidence that, on at least one occasion, GAF took steps to enforce its boycott. GAF salesmen Sal Granfort and Doug Collins warned DiNaso & Sons, a roofing and siding distributor located in Staten Island, New York, not to resell its product to Rossi. After DiNaso & Sons ignored their warnings, GAF raised DiNaso's prices by $1.00/unit, arguably in retaliation. Similarly, when Rossi contacted Stroeber Supply, another northern New Jersey distributor, to see if it would sell GAF product to him, Larry Hammershock of Stroeber told a Rossi Roofing employee that Stroeber had already been told by GAF not to sell GAF product to Rossi Roofing. Hammershock defied GAF and sold to Rossi Roofing anyway, but at a higher price.

There is also evidence that GAF extended the boycott to buying groups like HWI and Servistar which Rossi began to use, in addition to distributors like Stroeber and DiNaso, to try to circumvent the GAF boycott.16 To this end, Rossi joined HWI in July 1989 and placed an order for GAF product. Membership in HWI ordinarily should have allowed Rossi to purchase products from all of HWI's suppliers, including GAF. Likewise, GAF normally supplied its products to all HWI members, regardless of whether they appeared on GAF's own customer list. Notwithstanding this, when a Rossi Roofing driver went to GAF's facility on July 27, 1989, to pick up the GAF product ordered through HWI, GAF would not release it. After several hours of wrangling over the order, Rossi eventually spoke with Krusa, who had given the order not to release the GAF product. Krusa told Rossi "I am not selling to you. The distribution is filled. GAF requires no other distributors." Rossi replied that GAF was not really selling to Rossi Roofing, but rather to HWI, to which Krusa responded, "We are not selling to you." After this dramatic exchange, Dave Heine of HWI remarked that he had never seen anything like this in his ten years working at the buying group. App. at 2596, 3513.

In yet another effort to obtain GAF product and circumvent the boycott, Rossi used Far Hills Lumber and Hardware ("Far Hills"), a start-up hardware store of which he was a principal, to place orders through the buying group Servistar. See supra § II.B.2.a and infra § II.B.2.c. Rossi was able to purchase one order of $30,000 worth of GAF product on August 2 and 3, 1989. However, after GAF and Standard found out that Rossi had used Far Hills and Servistar to get GAF product, see infra § II.B.2.c, GAF refused to fill Far Hills' second order for $456 of GAF product.

Rossi has also adduced evidence that GAF and Standard coordinated to ensure that Rossi was not getting any GAF product. See supra § II.B.2.a. Rossi developed evidence that Licciardello of Standard confirmed with Gessner of GAF that GAF was not selling to Rossi, and there is evidence that, after seeing GAF product in front of Rossi Roofing, Licciardello called and was reassured by GAF that the load was not for Rossi but bound for Walmart on a Jentar truck. See id. In addition, there is the statement made by Licciardello after he learned that Rossi Roofing had been getting GAF product through Far Hills and Servistar that " 'that's the last time we're going to be seeing any GAF across the street.' They got the--they were getting the loads through [Far Hills], which is [Servistar]. That's how Joe Rossi was getting GAF and he's [Licciardello] going to put an end to that. 'Never going to see another GAF load across the street.' " See supra § II.B.2.a.(d) Pretextual Excuses

Finally, Rossi argues that GAF used pretextual excuses to explain why it refused to supply Rossi, and that this use of pretext is further circumstantial evidence of the conspiracy he alleges. See Fragale, 760 F.2d at 474 (pretextual excuses are circumstantial evidence that can disprove the likelihood of independent action). The first excuse is that Rossi was not needed because GAF had adequate distribution. Rossi notes that, despite Krusa's contention that everyone in his office knew that he had "adequate distribution" in New Jersey, neither his boss, Peter Bacchione, nor his employees, Lorraine Campbell, Ruth Rogers, Mary Lou Sperr, and Bob Tafaro had ever heard of this policy. Even Krusa admits that GAF had never refused to fill an order through a buying group like Servistar because its distribution was allegedly full.

This "adequate distribution" excuse is just the "flip side" of Rossi's contention that GAF was acting in contravention of its open distribution policy, and for the same reasons that there is a genuine issue whether GAF's policy was to supply all distributors who wished to purchase its products, there is also a genuine issue of material fact whether the "adequate distribution" justification Krusa gave to Rossi was legitimate or simply pretextual. We note again that GAF supplied its roofing product to at least 34 of the 39 distributors in the northern New Jersey marketplace, but not to Rossi.

GAF's second excuse, which Rossi submits was also pretextual, was that GAF had a product shortage and therefore could not supply any new distributors. Rossi contends that there is a genuine issue of material fact as to the validity of this excuse because Bacchione, GAF's national sales manager, testified that he could recall no problems in filling customer orders for GAF product in 1989, despite the fact that this would have been a matter within his job responsibilities. In addition, Rossi argues that the only document GAF has been able to produce to corroborate Krusa's claim that GAF product was in short supply in 1988 and 1989 was a memorandum dated August 11, 1989. Rossi submits that this memorandum should not be considered conclusive for the purposes of summary judgment because it was written almost nine months after GAF had decided not to supply Rossi Florence. GAF counters that the memorandum refers to the product shortage as a "continuing" issue, and therefore that summary judgment is appropriate.

The critical language in the memorandum is:

We continue to have an im-balance of inventory between Baltimore and So. Bound Brook. The lack of warehousing has been a very critical issue, causing the im-balance in inventory.

We are receiving more calls, on a daily basis, from customers in the southern half of the district complaining of our lack of product and the congestion of trucks and also the length of time it takes to get loaded at the Baltimore Plant.

Our reading of the document is that it is ambiguous and therefore insufficient to command summary judgment. For example, it is unclear whether the memorandum refers to an overall GAF product shortage or just a warehousing "imbalance" that was temporarily interfering with delivery to the southern half of Krusa's territory. Also, while the memorandum refers to the problem as a "continuing" one, there is no indication what that means. On summary judgment, viewing the evidence in a light most favorable to Rossi, he has established a genuine issue of fact whether both the "adequate distribution" and the "product shortage" excuses were pretextual.

(e) Conclusion

To summarize, we find that Rossi has adduced competent evidence that GAF: (1) responded to distributor complaints in the past; (2) singled out Rossi as one of the few distributors out of a large number in northern New Jersey not to receive GAF product; (3) acted in contravention of its own established open distribution policy in dealing with Rossi; (4) threatened and punished distributors who resold to Rossi; (5) refused to supply Rossi through buying groups; (6) implemented an unprecedented policy prohibiting transshipment of GAF product to Rossi; (7) cooperated with Standard in monitoring and enforcing the boycott; and (8) offered pretextual excuses to explain its behavior. Examining the totality of this evidence, it is sufficient to support a reasonable inference that GAF was acting in concert with Standard and Arzee to boycott Rossi.

Particularly forceful is the evidence that GAF prohibited distributors from trans-shipping GAF product to Rossi and that GAF prevented Rossi from purchasing its products from buying groups. These actions simply do not make sense in light of GAF's asserted justifications for its behavior vis a vis Rossi. For example, if there were truly a product shortage in northern New Jersey, presumably GAF would then have cut off supply to all Servistar and HWI members who were not on GAF's approved customer list to ensure that its larger distributors like Standard and Arzee would not suffer from the short supply. Yet, GAF supplied Far Hills, also an entity that was not on GAF's customer list, until it discovered that Far Hills was under Rossi's control. Moreover, the product shortage excuse is not consistent with GAF's claim that it unilaterally implemented a policy precluding trans-shipment of product at the distributor level. Assuming that GAF product was scarce, GAF would understandably want to ensure that its favored distributors received it ahead of all others. However, once GAF decided how it would allocate among its approved distributors whatever amount of GAF product existed, it is difficult to conceive of a legitimate reason why GAF would care whether that distributor used the product or resold it to Rossi Roofing at a profit.

Additionally, the product shortage justification does not explain why GAF would sell Droesch as much GAF product as he wanted in Long Island but would not allow him to trans-ship that product to New Jersey. Similarly, it is hard to comprehend why GAF would continue to fill $30,000 orders, obviously commercial-sized purchases, to buying group members in northern New Jersey, if it was truly believed that it had adequate distribution in that market. One explanation of this behavior is that GAF was acting in concert with Standard, Arzee, and Allied to boycott Rossi and force him out of business.

For the reasons described above, Rossi has met his burden of adducing evidence that tends to exclude the possibility of independent action, and hence we will reverse the district court's order granting summary judgment in favor of GAF.

c. Servistar

In contrast to the defendants discussed above, we will affirm the district court's grant of summary judgment in favor of Servistar because Rossi has failed to introduce either direct or circumstantial evidence that tends to exclude the possibility that Servistar acted independently rather than joining the conspiracy against Rossi.

Servistar's involvement in this case stems from its refusal to honor Rossi's second purchase request for $456 of GAF product on August 11, 1989. Rossi had already obtained a little over $30,000 of GAF product on August 8 and 9, 1989, via his Far Hills account with Servistar, which was resold to Rossi Roofing. Two days later, when Rossi attempted to order a second batch, Servistar did not fill it, claiming that GAF had cut Far Hills off from obtaining GAF product. Rossi contends that after he received the first order of GAF product, Standard and Arzee discovered how he had circumvented the blockade, notified GAF, and that GAF then enlisted Servistar to join the group boycott and cut off this new avenue of supply. Rossi offers three pieces of evidence to support this allegation: (1) a discussion he had with Jim Cherbonneau of Servistar in which Cherbonneau told him that GAF did not want Servistar to ship its product to Rossi and that GAF would not supply Rossi through his Servistar account;17 (2) Servistar's curious and sudden change of mind, selling Rossi $30,000 of GAF product one day and refusing a minuscule $456 order two days later; and (3) Servistar's use of the allegedly pretextual excuse that Far Hills had credit problems to justify its refusal to deal.

Rossi's only direct evidence, the phone conversation with Cherbonneau, is not evidence of Servistar's conspiratorial involvement. Cherbonneau said that "GAF would not sell product to Servistar to go to--through [Far Hills] to me." Cherbonneau's statement, while not precluding concerted action, is evidence only of a unilateral decision by GAF to not supply Rossi through any means (or a multilateral conspiracy that did not include Servistar). Additionally, it is undisputed that Servistar could not force GAF to supply it or its members with GAF product. Unlike other products Servistar supplied, Servistar neither stored GAF product in its warehouses nor had the contractual right to compel GAF to supply the product. The Servistar-GAF purchasing agreement did not obligate GAF to accept all of Servistar's members' orders.

Because Servistar provided GAF product to its members on what is known in the industry as a "drop shipment" basis, it had no control over whether its suppliers would actually deliver their products to its members. The "drop shipment" relationship between Servistar and GAF meant that when a Servistar member placed an order with Servistar for GAF product, Servistar would forward that order to GAF. The member would then go to the GAF warehouse to pick up the GAF product directly from GAF, not Servistar. GAF then would invoice Servistar for the purchase, and Servistar would pay GAF. Subsequently, Servistar would collect the amount due from its member. Using this "drop shipment" purchasing method, Servistar assists its members by: (1) negotiating group discounts from manufacturers, and (2) acting as the guarantor of its members' credit to those manufacturers. Thus, Servistar's role did not include pre-purchasing and warehousing of GAF product, and it had virtually no say over which of its members GAF chose to supply.

Under these circumstances, Rossi's claim that "at the request of GAF, Servistar refused to fill Far Hills' next order for $450 because Far Hills had resold it to Rossi Roofing," is not supported by Rossi's own testimony. As described above, according to the undisputed evidence, GAF did not have to conspire with Servistar to boycott Rossi Roofing because GAF did not need Servistar's acquiescence to prohibit Far Hills or Rossi Roofing from buying its product through Servistar. Since there is no evidence that Servistar could overrule a unilateral GAF decision to refuse to supply a Servistar member, we cannot reasonably infer on the basis of such ambiguous evidence that Servistar and GAF agreed to refuse to sell to Far Hills. See International Logistics Group Ltd. v. Chrysler Corp., 884 F.2d 904, 907 (6th Cir.1989) (no credible conspiracy is alleged where a manufacturer imposing distribution restraints does not need agreement or acquiescence from its distributors in formulating marketing conditions for its product); 6 Phillip E. Areeda, Antitrust Law p 1402b4 (1986) ("discussions, suggestions, recommendations, and the giving of information do not indicate any conspiracy where the actor imposing the alleged restraint does not wish or need the acquiescence of the other party or any quid pro quo from him").

Similarly, Rossi's allegation that Servistar made no effort to require GAF to fill the order of its member Far Hills does not support his theory of conspiracy. Without direct evidence (or other strong circumstantial evidence) of concerted action by Servistar and GAF, we cannot draw an inference of an unlawful conspiracy from the equivocal nature of Servistar's decision not to make what would most likely have been a futile effort to encourage GAF to sell to Rossi. Servistar's refusal to disrupt its relationship with GAF because GAF unilaterally (from Servistar's perspective) refused to deal with Rossi is clearly "as consistent with permissible competition as with illegal conspiracy," Matsushita, 475 U.S. at 588, 106 S. Ct. 1348 (citations omitted), and is not evidence of a "conscious commitment to a common scheme." Monsanto, 465 U.S. at 764, 104 S. Ct. 1464. We note in this regard that there is no evidence that Servistar was on notice that GAF was part of a conspiracy to boycott Rossi Roofing. Thus, from Servistar's point of view, this was simply a unilateral refusal to deal. Indeed, even if Servistar did know that GAF was involved in an unlawful group boycott, its decision to continue relations with GAF would still not rise to the level of concerted action.

Without direct evidence with respect to Servistar, we must also consider whether Rossi's conspiracy theory is plausible, and whether inferring concerted action under these circumstances would have the effect of deterring significant procompetitive conduct. See Petruzzi's, 998 F.2d at 1233. Both of these considerations militate against inferring concerted action with respect to Servistar. Apart from the evidence discussed above that it would be unreasonable to infer that Servistar would conspire with GAF to do what GAF could do unilaterally (i.e. refuse to release GAF product to Rossi from GAF warehouses), it is similarly implausible that GAF, an extremely minor Servistar supplier, could "pressure" Servistar, a billion plus dollar buying cooperative, into joining the group boycott of Rossi Roofing, a small start-up roofing and siding distributor. Similarly, Rossi has adduced no evidence of a motive for Servistar to join the conspiracy. See Matsushita, 475 U.S. at 596-97, 106 S. Ct. 1348. Nothing in the record indicates that Servistar had any reason to support a conspiracy to increase or stabilize wholesale roofing prices in New Jersey, and, to repeat, there is simply no evidence of GAF leverage over Servistar.18

Perhaps most importantly, inferring a conspiracy from the slim circumstantial evidence would have the effect of deterring Servistar's significant procompetitive conduct in this as well as many other markets. As a wholesale purchasing cooperative, Servistar bolsters competition and increases economic efficiency by aggregating small purchasers thereby permitting them "to achieve economies of scale in both the purchase and warehousing of wholesale supplies, and also ensur[ing] ready access to a stock of goods that might otherwise be unavailable on short notice. The cost savings and order-filling guarantees enable smaller retailers to reduce prices and maintain their retail stock so as to compete more effectively with larger retailers." Northwest Wholesale Stationers, 472 U.S. at 295, 105 S. Ct. 2613. If we were to permit an antitrust violation to be inferred under the facts of this case, it would significantly impact the ability of Servistar to continue its procompetitive actions in the market.

Because Servistar could not compel GAF to sell to Far Hills, Servistar's only option in response to GAF's decision not to supply Far Hills would have been to somehow bring pressure to bear on the roofing manufacturer. Such action would undoubtedly adversely affect all Servistar members nationwide who were receiving improved pricing for GAF product through Servistar, especially if it led to the restriction or cessation of Servistar's purchasing agreement with GAF. Indeed, inferring concerted action in these circumstances could encourage Servistar to terminate relationships with every supplier that refused to sell to a particular Servistar member. This would deter Servistar's procompetitive activities and deny Servistar's members the significant benefits of cooperative membership.

Finally, Rossi submits that Servistar offered a pretextual excuse to explain its decision not to supply Far Hills with GAF product. Pretextual excuses, as noted, can disprove the likelihood of independent action. See Fragale, 760 F.2d at 474. Rossi challenges Servistar's explanation that it refused to supply the second order of GAF product to Far Hills because of Far Hills' credit problems. Although it appears that there are genuine issues of fact concerning Far Hills' credit-worthiness and its impact on Servistar's decision to refuse Rossi's second order of GAF product,19 considering Servistar's lack of motive to conspire, GAF's lack of any leverage over Servistar, and the fact that GAF did not need to enlist Servistar's help to boycott Rossi, this slim reed of pretext is simply not enough. In view of the procompetitive role Servistar plays in the market generally and concerned that we do not "chill the very conduct the antitrust laws are designed to protect," Matsushita, 475 U.S. at 594, 106 S. Ct. 1348, we conclude that Rossi has not met his burden here in opposing summary judgment, and therefore we will affirm the district court's order granting summary judgment in favor of Servistar.

d. Wood Fiber

Like GAF, Wood Fiber manufactures roofing products, including Structodek FS, which is widely used in certain commercial roofing applications. Unlike GAF, however, Wood Fiber is only tangentially involved in the alleged conspiracy with its activity centering around a single incident in which Rossi was frustrated in his attempt to purchase approximately $5,000 worth of Structodek FS. We will affirm the district court's grant of summary judgment in favor of Wood Fiber because, as with Servistar, Rossi has failed to introduce evidence that tends to exclude the possibility that Wood Fiber acted independently rather than joining the conspiracy against Rossi.

On June 6, 1989, Rossi Roofing ordered Structodek FS from Wood Fiber for its customer, Star Roofing. Wood Fiber quoted a price and a shipping date of July 5th to Rossi Roofing. On June 27, 1989, Karl Loser, Wood Fiber's sales representative in New Jersey, called and told Rossi Roofing's Mike Issler that Wood Fiber would not fill the order. As a result, Rossi Roofing lost the order for Structodek FS from Star Roofing. Rossi claims that Loser told him that Wood Fiber was being pressured by Standard and Arzee not to sell to him and that there was a "problem" with his pricing. Loser also told Issler that Wood Fiber had previously sold product to a small distributor on Long Island and suffered when Allied canceled orders in retaliation. Loser testified that he wanted to supply Rossi Roofing, but that his concerns that Rossi Roofing's competitors would retaliate "influenced" his decision not to supply Rossi Roofing.

Based upon these facts, Rossi asks us to infer that Wood Fiber participated in a conspiracy to boycott Rossi Roofing because it gave in to pressure and fear of retaliation by several of its distributors. It is well established that this kind of evidence, by itself, is legally insufficient to prove a conspiracy. See Monsanto, 465 U.S. at 763-64, 104 S. Ct. 1464; Sweeney, 637 F.2d at 111. In Sweeney, the plaintiffs contended that "the retailers' acts of complaining and [the defendant's] reaction to the complaints constituted concerted action in restraint of trade." Sweeney, 637 F.2d at 110. We rejected that argument and noted that "even if the appellants had demonstrated that [the defendant's] actions were in response to these complaints, such evidence alone would not show the necessary concerted action." Id. Similarly, in Monsanto, the Supreme Court opined that "[p]ermitting an agreement to be inferred merely from the existence of complaints, or even from the fact that termination came about 'in response to' complaints, could deter or penalize perfectly legitimate conduct." 465 U.S. at 763, 104 S. Ct. 1464. Thus, the Court held that " '[t]o permit the inference of concerted action on the basis of receiving complaints alone and thus to expose the defendant to treble damage liability would both inhibit management's exercise of independent business judgment and emasculate the terms of the statute.' " Id. at 764, 104 S. Ct. 1464 (quoting Sweeney, 637 F.2d at 111 n. 2).

We have explained at length supra why the claims against Standard, Arzee, and GAF survive, notwithstanding these precedents. However, because Rossi has not adduced evidence of anything other than the fact that Wood Fiber may have responded to pressure and threats from Standard and Arzee, we cannot infer the existence of concerted action involving Wood Fiber. The evidence adduced against Wood Fiber stands in stark contrast to the evidence against GAF. For example, Rossi has not adduced any evidence that Wood Fiber offered pretextual excuses, or prohibited transshipment of its product, or engaged in monitoring and enforcement of the alleged boycott. Without some additional evidence, a fact finder may not infer that Wood Fiber entered into an agreement to boycott Rossi Florence or Rossi Roofing, and therefore we will affirm the district court's order granting summary judgment in favor of Wood Fiber.

Having determined that Rossi has adduced sufficient evidence of a conspiracy to satisfy the first prong of the prima facie case with respect to the Standard defendants, the Arzee defendants, and GAF, we now consider whether Rossi has adduced sufficient evidence to satisfy the fourth prong, "that the plaintiffs were injured as a proximate result of that conspiracy." Tunis Bros., 763 F.2d at 1489.20

The district court concluded that even if Rossi had established the existence of an agreement, his claim still would fail because he had not established that the business losses he suffered were in any way related to that conspiracy. See Rossi v. Standard Roofing, Inc., 958 F. Supp. 976, 991 (D.N.J.1997). The court determined that Rossi's allegations--that the defendants prevented him from obtaining GAF and other roofing products he needed to compete and thereby stopped him from opening Rossi Florence and ultimately forced Rossi Roofing out of business--are unsupported in the record. The district court also concluded that Rossi's damages expert, Regan R. Rockhill, CPA, based his report upon unfounded assumptions that would force a trier of fact to use "guesswork and speculation" in determining what, if any, injury Rossi suffered as a result of the defendants' actions. See id. The court criticized the Rockhill Report for being nothing more than an impermissible "but for" damage model that erroneously ignored several important factors, including failing: (1) to consider that Rossi had no experience running his own business; (2) to analyze specifically what products were needed to assure a successful distributorship; and (3) to engage in any analysis of what harm, if any, was caused by the alleged antitrust violations as opposed to other factors, such as Rossi's management style or general business conditions. See id.

The district court accordingly held that Rossi had not presented sufficient evidence of damages such that a reasonable inference could be made connecting the injury with the defendants' conduct. For the reasons we will explain, we disagree with the court's conclusion that Rossi has not identified a genuine issue of material fact with regard to the proximate cause and damages element of his prima facie case.

To recover damages, an antitrust plaintiff must prove causation, described in our jurisprudence as "fact of damage or injury." See Danny Kresky Enters. Corp. v. Magid, 716 F.2d 206, 209 (3d Cir.1983). It is not necessary to show with total certainty the amount of damages sustained, just that the antitrust violation caused the antitrust injury suffered by the plaintiff. See Amerinet, Inc. v. Xerox Corp., 972 F.2d 1483, 1493 (8th Cir.1992); Danny Kresky, 716 F.2d at 211 ("the standard of causation requires only that plaintiff prove that defendant's illegal conduct was a material cause of its injury"). As the Supreme Court explained in Zenith Radio Corp. v. Hazeltine Research, Inc., 395 U.S. 100, 114 n. 9, 89 S. Ct. 1562, 23 L. Ed. 2d 129 (1969) (citations omitted) (emphasis in original):

[Plaintiff's] burden of proving the fact of damage under § 4 of the Clayton Act is satisfied by its proof of some damage flowing from the unlawful conspiracy; inquiry beyond this minimum point goes only to the amount and not the fact of damages. It is enough that the illegality is shown to be a material cause of the injury; a plaintiff need not exhaust all possible alternative sources of injury in fulfilling his burden of proving compensable injury under § 4.

Once causation is established, the jury is permitted to calculate the actual damages suffered using a " 'reasonable estimate, as long as the jury verdict is not the product of speculation or guess work.' " In re Lower Lake Erie Iron Ore Antitrust Litig., 998 F.2d 1144, 1176 (3d Cir.1993) (citing MCI Communications Corp. v. American Tel. & Tel. Co., 708 F.2d 1081, 1161 (7th Cir.1983)) (other citations omitted). Thus, in antitrust cases, there are ultimately two related, but distinct, inquiries to establish antitrust injury. First, the plaintiff must prove the fact of antitrust injury, as part of his prima facie case; then, he must make a showing regarding the amount of damages, in order to justify an award by the trier of fact. Concerning the former, courts apply the ordinary standard of proof, but with respect to the latter, the standard is somewhat relaxed. See In re Lower Lake Erie Iron Ore, 998 F.2d at 1176 ("[t]he relaxed measure of proof is afforded to the amount, not the causation of loss--the nexus between the defendant's illegal activity and the injuries suffered must be reasonably proven.") (citations omitted); see also Bigelow v. RKO Radio Pictures, 327 U.S. 251, 264-65, 66 S. Ct. 574, 90 L. Ed. 652 (1946) (holding that when the plaintiff cannot prove his damages by precise computation, the jury "may make a just and reasonable estimate of the damage based on relevant data, and render its verdict accordingly").

Under these standards, Rossi's antitrust claim does not suffer from the infirmities claimed by the district court. At the threshold, it is important to note that we need only concern ourselves with the first element of antitrust injury, causation. At this procedural juncture, reviewing the district court's grant of the defendants' motions for summary judgment, we are not, as we would be upon reviewing a jury verdict, determining whether a plaintiff has brought forth sufficient evidence to justify the actual damages awarded. Rather, here, all we are concerned with is whether Rossi has established that the defendants' "illegal conduct was a material cause of [his] injury." Danny Kresky, 716 F.2d at 211; see also Zenith Radio, 395 U.S. at 114 n. 9, 89 S. Ct. 1562.

We find two sources of evidence sufficient for Rossi to demonstrate fact of injury or causation: (1) evidence of specific lost transactions based upon Rossi's inability to purchase product; and (2) the Rockhill Damage Report. We discuss these in turn.

We have already explained that there is ample evidence in the record that Standard, Arzee, and GAF conspired to deny Rossi access to GAF product and prevent him from competing in the roofing and siding business in northern New Jersey. See supra § II.B.2.a & b. Also, there is evidence that, with a few exceptions, the defendants successfully prevented Rossi from obtaining GAF product. See id. Moreover, there is evidence that GAF product was highly desirable, if not critical, to Rossi's target customers. See supra § II.B.2.b(1). Finally, several of Rossi's former customers from his Standard days, including Sean Coffey, Francis Doherty, John Feher, Albert Logan, and Melvin Stanley, have testified that they would have done business with Rossi Roofing if he had access to the necessary products, primarily GAF product.

This evidence is enough by itself to satisfy Rossi's burden on causation for the purposes of summary judgment. Rossi has put forth evidence that the defendants' alleged conspiracy unlawfully prevented him from obtaining GAF product, and that he lost multiple sales as a result. Thus, if Rossi can successfully prove the existence of the conspiracy, he will have proved fact of injury. The case before us is not analogous to Van Dyk Research Corp. v. Xerox Corp., 478 F. Supp. 1268 (D.N.J.1979), a case upon which the district court relied, where the plaintiff failed to prove fact of injury primarily because it could not show that it lost even a single contract based upon the alleged unlawful practices of the defendant. See 478 F. Supp. at 1327.

In the same vein, Amerinet is not availing to the defendants either. In Amerinet, the Eighth Circuit concluded that the plaintiff had not shown antitrust injury or causation in large part because statements and assertions by its own damage expert "strongly suggest[ed] ... that [plaintiff's] decline was caused at least partly by, if not substantially or mainly by, other factors than [defendant's] alleged antitrust violations." Amerinet, 972 F.2d at 1495 (noting that the plaintiff's damage expert admitted that the plaintiff was in a period of decline prior to the defendant's alleged antitrust violations). In addition, the plaintiff in Amerinet was only able to show that, at most, the allegedly illegal activity was "one factor among many, and not a controlling or major factor" in specific potential clients' decisions not to purchase from the plaintiff. Id. at 1497. Therefore, the Eighth Circuit held that the plaintiff had not adduced sufficient evidence of element of causation to enable it to withstand summary judgment.

Here, Rossi's evidence is more substantial than in either Van Dyk Research or Amerinet. Rossi has proffered evidence from five specific customers that they would have purchased GAF product from Rossi if he had been able to sell it to them, and Rossi's inability to consummate those sales (leading to a loss of business and therefore injury) is a direct result of the alleged antitrust violation--the group boycott. In addition, Richard Droesch, Rossi's partner in the failed Rossi Florence venture, backed out of that venture at least in part based upon his understanding that the company would not be able to get the products it needed, particularly GAF product, to compete successfully in the market. For all these reasons, we believe that the record supports Rossi's allegations that he suffered antitrust injury, and that it was caused by the defendant's allegedly unlawful actions.

The district court also utterly rejected Rossi's damage expert, holding that his report was nothing more than a "but for" damage model that failed as a matter of law to support Rossi's damage allegations. We believe, however, that the Rockhill Report, when combined with the testimony concerning the five lost sales, is indicative of a larger pattern of loss and helps Rossi demonstrate causation. Thus, while the other damage evidence is enough alone to satisfy Rossi's summary judgment burden, for the guidance of the district court on remand, we nonetheless consider the Rockhill Report.

A typical "but for" damage model, like the one in Southern Pacific Com. Co. v. American Tel. & Tel. Co., 556 F. Supp. 825 (D.D.C.1982), aggregates the defendant's alleged violations and creates a hypothetical calculation projecting the plaintiff's profits and losses "but for" the defendant's antitrust violations. In Van Dyk Research, for example, this estimate was based upon an internal "task force" report created by the plaintiff projecting its own future performance. See 478 F. Supp. at 1327. The plaintiff then compares this hypothetical figure with its actual performance to calculate its damages. Courts usually highlight two problems with models created using this methodology.

First, they do not attempt to measure the particularized effects of any specific alleged illegal practices, but rather rely on an aggregation of injury from all factors. See Southern Pacific, 556 F. Supp. at 1092. Second, their hypothetical "but for" calculations usually rely upon unrealistic ex ante assumptions about the business environment, such as assumptions of perfect knowledge of future demand, future prices, and future costs that tend to overstate the plaintiff's damage claim. See id. at 1092-93 (pointing out many difficulties not caused by the defendants that negatively impacted plaintiff's profitability yet were not accounted for in the "but for" damage model). Thus, using a "but for" damage model arguably makes it impossible for the trier of fact to determine what, if any, injury derived from the defendant's antitrust violations as opposed to other factors, and courts sometimes reject such models as the basis of either causation or amount of injury. See Southern Pacific, 556 F. Supp. at 1090, 1098; Van Dyk Research, 478 F. Supp. at 1327.

The Rockhill Report is in many respects a "but for" damage model because it does not deal with the particularized effects of specific injuries, but rather aggregates all of Rossi's damages into one figure. Relying on Van Dyk Research and Southern Pacific, defendants argue that all "but for" models should be precluded as a matter of law from serving as a basis for antitrust causation and damage calculation. We do not agree with the defendants' reading of these cases (and, at all events, are not bound by them), which we conclude only stand for the proposition that some, not all, "but for" models are too speculative and must be precluded as a matter of law. The Rockhill Report, as we shall see, is much less speculative and does not suffer from many of the flaws in the damage models discussed in Van Dyk Research and Southern Pacific, and thus it is not comparable with them.

Rockhill made two major assumptions in calculating the damages Rossi suffered because of his inability to procure products. First, he estimated that Rossi Florence and/or Rossi Roofing would have achieved the same pattern of sales revenues (and revenue growth) beginning in 1989 and extending to 2008 that ABC's Morristown sales branch actually achieved from 1990-1993, operating out of the same location, with Rossi as branch manager. Rossi makes a strong argument that this estimate took into account the poor general business conditions that existed at the time, as well as any other extrinsic factors not related to the defendants' alleged boycott, because Rockhill based his estimate upon actual sales figures Rossi was able to achieve competing against the same firms, selling the same products at the same location to the same customers under the actual business conditions that existed at the time.21 The second major assumption in the Rockhill Report is that Rossi would have been able to manage Rossi Florence and Rossi Roofing in the manner that he had run Standard's Morristown branch from 1974-1987. Rockhill used Standard's Morristown branch financial statements to develop 14-year averages for cost of sales, payroll expenses, equipment expenses, and administrative expenses (as a percentage of total sales) and applied them to the sales estimate. This kind of estimate, while perhaps not one upon which we would base our own personal investment decisions, nevertheless is sufficient to establish causation (especially when considered in conjunction with the five lost transactions).22

On the subject of the Rockhill Report, we add that the defendants' criticism that the report is flawed as a matter of law because it improperly mixes data using "a variety of sources including the historic operations of Standard; ABC actual data; input from Mr. Rossi; and judgment" is unavailing. Rockhill used actual data to support his estimates, and thus they are based upon a "reasonable foundation." See Danny Kresky, 716 F.2d at 213. We do not suggest that Standard's problems with the report are baseless, only that they constitute genuine issues of material fact and should also be argued before the trier of fact.

Finally, the defendants attack the evidence supporting Rossi's assertion of damages on several other bases. Defendants submit that Rossi Florence and Rossi Roofing failed because: (1) they were start-up operations, (2) they were founded during one of the worst recessions ever to hit the New Jersey housing market, (3) Rossi, as a manager, failed to control his costs, and/or (4) Rossi worked on other ventures to the detriment and ultimate failure of both companies. One or more of these reasons, particularly the theory that it was the recession, not a conspiracy, which mortally wounded Rossi's business efforts, might explain Rossi's failure in the roofing and siding business in northern New Jersey, and could conceivably result in a verdict for the defendants at trial. They are, however, unavailing to the defendants at this stage of the case because they all involve factual disputes that need to be resolved by the trier of fact, not by this court on a motion for summary judgment.

Standard also argues that Rossi failed to establish causation because an essential element in causation involves proving that there are no comparable substitutes for the desired product--here, GAF product. See Elder-Beerman Stores Corp. v. Federated Dep't Stores, Inc., 459 F.2d 138, 148 (6th Cir.1972). This is another factual issue that Standard may argue to the jury. As we have explained above, we are satisfied that Rossi's own testimony and that of several of his witnesses are sufficient to establish that GAF product was, for practical purposes, unique and highly desired in this market. See supra § II.B.2.b(1).

In sum, Rossi has established a prima facie case of antitrust injury with respect to Standard, Arzee, and GAF. He has adduced evidence of specific lost transactions showing causation or fact of injury, which is bolstered by an expert damage report that is not overly speculative as a matter of law. The combination of this evidence, while not conclusive, provides enough of a foundation that an eventual finder of fact would be justified in making a "just and reasonable inference" of the damages Rossi may have suffered as a result of the defendants' allegedly unlawful activities.

IV. STATE LAW TORTIOUS INTERFERENCE WITH CONTRACTUAL AND

The district court dismissed Rossi's state law tortious interference claims against defendants with no discussion. It very well may be, as some of the defendants suggest, that the district court concluded when it dismissed Rossi's state law claims that Rossi had not shown any wrongful or intentional conduct designed to interfere with alleged contractual or prospective contractual relationships. If that is the case, then based upon our disposition here, the state law claims will likely have to be reinstated with respect to the Standard defendants, the Arzee defendants, and GAF since we have found that there is sufficient evidence of their participation in an unlawful conspiracy to boycott Rossi. However, the district court may have had some other reason for dismissing these claims of which neither we nor the parties before us is aware. Our jurisprudence requires district courts in this circuit to accompany grants of summary judgment with an explanation sufficient to permit the parties and this court to understand the legal premise for the court's order. See Vadino v. A. Valey Eng'rs, 903 F.2d 253, 257-60 (3d Cir.1990). We will therefore reverse the district court's order dismissing the state tortious interference claims against all defendants and remand them to the district court for further consideration and explanation consistent with this opinion.

For the foregoing reasons, we will affirm the district court's judgment on the federal antitrust issues with respect to Servistar and Wood Fiber, but reverse on those issues with respect to the Standard defendants, the Arzee defendants, and GAF. We will also reverse the district court's judgment dismissing the state claims with respect to all defendants. The case will be remanded for further proceedings consistent with this opinion.