MEMORANDUM AND ORDER RE: MOTION FOR SUMMARY JUDGMENT

WILLIAM B. SHUBB, District Judge.

Plaintiff Louis Mocettini brought this action against defendant Kenworth Truck Company, a division of PACCAR, Inc., after a grab handle he used to enter and exit a truck manufactured by defendant allegedly rolled in his grip and caused him to fall from the vehicle. Plaintiff seeks damages for his resulting injuries under parallel theories of negligence and strict products liability. Defendant now moves for summary judgment pursuant to Federal Rule of Civil Procedure 56.

I. Factual and Procedural History

On April 7, 2011, plaintiff was employed by Reliable Trucking ("Reliable") as a driver of commercial trucks. (Mocettini Dep. at 29:8-10 (Docket No. 42-1).) Because his regularly assigned truck was being serviced, Reliable assigned plaintiff to drive truck 15039 for the first time that day. (See id. at 29:11-30:6.) Reliable had purchased truck 15039 in March 2006 from defendant, who manufactured it in January 2006. (Lalley Dep. at 14:24-25 (Docket No. 42-14); Ferderer Dep. at 38:24-39:1 (Docket No. 42-9).) The truck featured a grab handle located next to the driver's door to aid truck operators in entering and exiting the cab of the vehicle. (Ferderer Dep. at 57:16-58:4.) The grab handle's design consisted of three elements: (1) a long, cylindrical steel tube, (2) two aluminum brackets located at either end of the tube, and (3) set screws that ran through the brackets and pressed against the tube. (Id.; see Perlee Decl. Ex. 10 (Docket No. 42-10).) When fully tightened, the screws were designed to hold the tube in place by pushing against it and creating a friction bond. They did not penetrate it. (Id.)

That day, plaintiff allegedly used the grab handle to enter and exit the vehicle three times without incident. (See Mocettini Dep. at 50:6-52:2, 99:4-17.) On the fourth time, however, the driver's side grab handle allegedly spun in his hand, causing him to lose his grip and fall backwards. (Id. at 65:1-14, 67:4-25.)

After plaintiff reported what had happened, two Reliable employees checked the grab handle and found that they were able to spin the steel tube in their hands. (See Lalley Dep. at 31:10-32:2; Maesetto Dep. at 24:20-24 (Docket No. 42-15).) To prevent future spinning, one employee drilled holes through the mounting brackets and the tube, then inserted additional sheet metal screws to affix the tube to the brackets. (See Lalley Dep. at 31:10-32:18; Maesetto Dep. at 12:12-16:9, 18:17-19:16, 23:10-24:24.)

Two years later, on November 13, 2013, experts employed by both parties disassembled and examined the grab handle in anticipation of this action. (See Frederer Dep. at 18:8-13, 66:9-67:14 (Docket No. 36-4); Buske Dep. at 51:7-52:24 (Docket No. 42-3); Kelkar Dep. at 31:4-32:10 (Docket No. 42-12).) They found marks on the steel tube suggesting that it had rotated more than once. (See id.) The parties dispute whether these marks show that the tube had rotated prior to the day of plaintiff's fall or were made thereafter. (See Def.'s Mem. at 1 (Docket No. 34); Pl.'s Opp'n at 6 (Docket No. 39).)1 The parties also found that one of the handle's set screws was missing at the time of inspection. (See Buske Dep. at 32:17-20.) Plaintiff does not know whether the screw was missing at the time of his injury. (Pl.'s Resp. to Def.'s First Req. for Admis. No. 4.)

On April 3, 2013, plaintiff filed a Complaint alleging negligence and strict products liability claims against defendant in the Superior Court of the State of California. (Notice of Removal ¶ 1 (Docket No. 1-1); Compl. at 1-3.) Defendant removed the action to federal court on the basis of diversity jurisdiction pursuant to 28 U.S.C. § 1441, certifying that it meets the requirements of 28 U.S.C. § 1332 because plaintiff is a resident of California, defendant is a Delaware corporation with its principal place of business in Bellevue, Washington, and the action exceeds the amount-in-controversy requirement. (Notice of Removal ¶¶ 3, 6-8). Defendant seeks summary judgment on each of those claims.

II. Legal Standard for Summary Judgment

Summary judgment is proper "if the movant shows that there is no genuine dispute as to any material fact and the movant is entitled to judgment as a matter of law." Fed. R. Civ. P. 56(a). A material fact is one that could affect the outcome of the suit, and a genuine dispute is one that could permit a reasonable jury to enter a verdict in the non-moving party's favor. Anderson v. Liberty Lobby, Inc., 477 U.S. 242, 248 (1986). The party moving for summary judgment bears the initial burden of establishing the absence of a genuine issue of material fact and can satisfy this burden by presenting evidence that negates an essential element of the non-moving party's case. Celotex Corp. v. Catrett, 477 U.S. 317, 322-23 (1986). Alternatively, the moving party can demonstrate that the non-moving party cannot produce evidence to support an essential element upon which it will bear the burden of proof at trial. Id.

Once the moving party meets its initial burden, the burden shifts to the non-moving party to "designate `specific facts showing that there is a genuine issue for trial.'" Id. at 324 (quoting then-Fed. R. Civ. P. 56(e)). To carry this burden, the non-moving party must "do more than simply show that there is some metaphysical doubt as to the material facts." Matsushita Elec. Indus. Co. v. Zenith Radio Corp., 475 U.S. 574, 586 (1986). "The mere existence of a scintilla of evidence . . . will be insufficient; there must be evidence on which the jury could reasonably find for the [non-moving party]." Anderson, 477 U.S. at 252.

In deciding a summary judgment motion, the court must view the evidence in the light most favorable to the non-moving party and draw all justifiable inferences in its favor. Id. at 255. "Credibility determinations, the weighing of the evidence, and the drawing of legitimate inferences from the facts are jury functions, not those of a judge . . . ruling on a motion for summary judgment...." Id.

III. Discussion

Defendant makes three basic arguments in support of its motion for summary judgment: (1) plaintiff cannot prove the grab handle's design caused his injury, (2) plaintiff cannot prove this particular risk was "known or knowable" at the time it distributed the handle, and (3) plaintiff cannot prove the handle differed from its intended design at the time it was made. (See Def.'s Mem. at 8-14.)2

A. Whether Defendant's Design Caused Plaintiff's Injury

Plaintiff alleges that defendant violated its duty of care by negligently designing the truck's grab handle, (Compl. ¶¶ 1-8.), and that the distribution of defendant's defective grab handle design supports strict products liability, (Compl. ¶¶ 9-13). Defendant seeks summary judgment on both these claims for essentially the same reason: plaintiff cannot prove that any alleged negligence or defective design defect caused his injuries. (Def.'s Mem. at 9-10, 13-14.)

1. California's Substantial Factor Test

As an element of both negligence and strict liability claims, California law requires the plaintiff to prove that the defendant's conduct was a "substantial factor" in causing a plaintiff's injury. Rutherford v. Owens-Illinois, Inc., 16 Cal.4th 953, 968 (1997) (stating that California has adopted the substantial factor test for cause-in-fact determinations); see also Altman v. HO Sports Co., 821 F.Supp.2d 1178, 1193 (E.D. Cal. 2011) (Ishii, J.) ("[A] manufacturer is liable only when a defect in its product was a legal cause of injury, that is, when the defect is a substantial factor in producing the injury." (citing Soule v. Gen. Motors Corp., 8 Cal.4th 548, 572 (1994)). "The substantial factor standard is a relatively broad one, requiring only that the contribution of the individual cause be more than negligible or theoretical." Bockrath v. Aldrich Chem. Co., 21 Cal.4th 71, 79 (1999) (quoting Rutherford, 16 Cal. 4th at 978).

Experts employed by both parties testified that the screws used in defendant's grab handle design will eventually loosen over time as a consequence of the handle's use. (See Buske Dep. at 30:19-31:25; Kelkar Dep. at 15:2-10.) Plaintiff's expert, Scott Buske, testified in particular that "[defendant] should anticipate that the truck is going to be driven down the road and experience vibration and whatnot, and that a set screw. . . might come loose and come out." (Buske Dep. at 34:3-7.) Loose set screws will allow the handle's tube to rotate—the alleged cause of plaintiff's injury. (Ferderer Dep. at 57:8-58:4.) At a minimum, this testimony raises a genuine dispute of material fact as to whether defendant's design contributed as a substantial factor in causing plaintiff's injury.

2. Reliance's Negligence, If Any, Does Not Supersede

Despite this evidence, defendant maintains that summary judgment is still appropriate because a third party's "superseding" actions absolve it of liability. (Def.'s Mem. at 9-10.) This argument requires the court to consider the traditional distinction between the intervening and superseding actions of a third party: "[A]n actor . . . is not relieved of liability because of the intervening act of a third person if such act was reasonably foreseeable at the time of his negligent conduct." Landeros v. Flood, 17 Cal.3d 399, 411 (1976) (quoting Vesely v. Sager 5 Cal.3d 153, 163 (1971)). However, a superseding cause of injury breaks the chain of causation that would otherwise flow from an initial actor's conduct, clearing that initial actor of liability. Hardison v. Bushnell, 18 Cal.App.4th 22, 27 (5th Dist. 1993).

An intervening force becomes a superseding cause if it "is highly unusual or extraordinary, not reasonably likely to happen and hence not foreseeable." Jackson v. Ryder Truck Rental, Inc., 16 Cal.App.4th 1830, 1848 (3d Dist. 1993) (quoting 6 Witkin, Summary of Cal. Law § 975 (9th ed. 1988)). It is not enough to simply label a third party's intervening behavior negligent; that negligence must be "highly extraordinary." Stewart v. Cox, 55 Cal.2d 857, 864 (1961) ("[T]he fact that an intervening act of a third person is done in a negligent manner does not make it a superseding cause if a reasonable man . . . would not regard it as highly extraordinary that the third person so acted...."); see also Perez v. VAS S.p.A., 188 Cal.App.4th 658, 685 (2d Dist. 2010) ("[P]roduct misuse may serve as a complete defense when the misuse was so unforeseeable that it should be deemed the sole or superseding cause." (internal quotation marks and citations omitted)); Martinez v. Vintage Petroleum, Inc., 68 Cal.App.4th 695, 701 (2d Dist. 1998) ("[F]oreseeable intervening ordinary negligence will not supersede but such negligence, if `highly extraordinary,' will supersede.").

Under California law, superseding cause is an affirmative defense, and defendant has the burden of proving that an intervening act was extraordinary enough to supersede. See, e.g., Maupin v. Widling, 192 Cal.App.3d 568, 578 (2d Dist. 1987) ("[Defendant] had the burden to prove that Carlson's behavior in accelerating was `highly extraordinary' in order to cut off liability." (quoting BAJI No. 3.79 (7th ed. 1986))).

Defendant argues that Reliable failed to ensure the grab handle's screws remained tightened and that this failure constitutes a superseding cause of plaintiff's injury because "[i]t is not reasonable or foreseeable." (Def.'s Mem. at 9-10.) As its sole explanation for why the failure to tighten screws is unforeseeable, defendant points to state and federal laws and industry standards requiring owners to properly maintain their vehicles. (Id. at 9-10.) But the fact that Reliable may have violated some law or notion of professional conduct does not make that violation per se unusual or extraordinary as a matter of law.3 See Bigbee v. Pac. Tel. and Tel. Co., 34 Cal.3d 49, 58 (1983) ("If the likelihood that a third person may act in a particular manner is the hazard . . . which makes the actor negligent, such an act whether innocent, negligent, intentionally tortious, or criminal does not prevent the actor from being liable for harm caused thereby.") (emphasis added).

And defendant has not otherwise shown as a matter of law that the failure to tighten the grab handle's screws was so unforeseeable or extraordinary that a reasonably thoughtful person would not take it into account. See id. at 57. Accordingly, the court cannot conclude that negligence or misuse on Reliance's part, if any, constitutes a superseding cause, and it must deny defendant's request for summary judgment on these claims.

B. Whether this Particular Risk was "Known or Knowable" at the Time of Distribution

To prevail on a failure-to-warn claim in negligence or strict products liability, plaintiffs must prove "that the defendant did not adequately warn of a particular risk that was known or knowable in light of the generally recognized and prevailing best scientific and medical knowledge available at the time of manufacture and distribution." Anderson v. Owens-Corning Fiberglas Corp., 53 Cal.3d 987, 1002 (1991); see also Rosa v. Taser Int'l, Inc., 684 F.3d 941, 946 (9th Cir. 2012) ("California law places a duty on manufacturers to warn of a `particular risk' if it is `known or knowable . . . at the time of manufacture and distribution.'" (quoting Conte v. Wyeth, Inc., 168 Cal.App.4th 89, 85 (1st Dist. 2008)) (emphasis omitted). Under the "knowable" element of this approach, "[a] manufacturer is held to the knowledge and skill of an expert in the field; it is obliged to keep abreast of any scientific discoveries and is presumed to know the results of all such advances." Carlin v. Superior Court, 13 Cal.4th 1104, 1113 n.3 (1996).

The California Supreme Court has stressed the requirement that a risk be "known or reasonably scientifically knowable at the time of distribution," Anderson, 53 Cal. 3d at 999, because "eliminating the knowledge component had the effect of turning strict liability into absolute liability," id. at 997 (discussing the evolution of the failure-to-warn claim in California courts). To place an obligation on manufacturers to warn of unknown or unknowable risks would "recast the manufacturer in the role of an insurer." Id. at 998 (quoting Oakes v. E.I. Du Pont de Nemours & Co., 272 Cal.App.2d 645, 650-51 (3d Dist. 1969)).

Defendant argues for summary adjudication on the basis that there is no evidence that it had "actual or constructive knowledge" that its grab handle could rotate. (Def.'s Mem. at 14.) The court disagrees. Although the record contains no evidence that defendant actually knew that its handles might rotate, there is ample evidence to suggest that the risk was reasonably "knowable" at the time of manufacture. See Anderson, 53 Cal. 3d at 1002. Defendant's expert, Rajeev Kelkar, testified that set screws like those in defendant's design will not remain tight over the life of a truck and that "the screws will at some point start to loosen." (Kelkar Dep. at 15:2-10.) Plaintiff's expert, Scott Buske, stated that "[defendant] should anticipate that the truck is going to be driven down the road . . . and that a set screw . . . which is only frictionally holding it . . . might come loose and come out." (Buske Dep. at 34:3-7.) Given that defendant has been using this grab handle design for 23 years, (Def.'s Mem. at 14), a trier of fact might use this evidence to infer that defendant learned or could have reasonably learned that screws might come loose before January 2006, when it manufactured the truck in question.

The record also contains reason to conclude that the risk of a set screw coming loose or the grab handle rotating was "reasonably scientifically knowable." Carlin, 13 Cal. 4th at 1113 n.3. Buske testified that mechanical engineers prefer designs that hold handles in place using "positive contact"— "where something actually has to break or fail"—rather than a frictional contact like the one employed in defendant's design. (Buske Dep. at 31:18-25.) While this testimony does not conclusively establish what a mechanical engineer would have known in January 2006, it at least raises a genuine dispute of material fact on the question.

Because the record contains genuine disputes of material fact regarding whether defendant reasonably could have known that its grab handle design would rotate, the court must deny defendant's request for summary judgment on these claims.4

C. Whether Defendant's Grab Handle Differed from its Intended Design

A manufacturing defect occurs when "the defective product is one that differs from the manufacturer's intended result or from other ostensibly identical units of the same product line." Barker v. Lull Eng'g Co., 20 Cal.3d 413, 429 (1978) (discussing differences between manufacturing defects and design defects). It requires a showing that the product did not conform to the manufacturer's design at the time of manufacture. See Garrett v. Howmedica Osteonics Corp., 214 Cal.App.4th 173, 190 (2d Dist. 2013) ("[A] product has a manufacturing defect if the product as manufactured does not conform to the manufacturer's design.").

Nothing in the record establishes the existence of a manufacturing defect. (Def.'s Mem. at 11.) Summary judgment is appropriate "against a party who fails to make a showing sufficient to establish the existence of an element essential to that party's case, and on which that party will bear the burden of proof at trial." Celotex, 477 U.S. at 322. "`[S]o long as the losing party was on notice that [it] had to come forward with all of [its] evidence,' summary judgment can properly be entered." MAI Sys. Corp. v. Peak Computer, Inc., 991 F.2d 511, 520 (9th Cir. 1993) (quoting Celotex, 477 U.S. at 326).

Plaintiff bears the burden of proving at trial that the grab handle differed from its design at the time it was made. Although the parties agree that one set screw was missing at the time they inspected the grab handle, (See Buske Dep. at 32:17-20), plaintiff has produced no evidence that the screw was missing at the time of manufacture and offers no reason for thinking that the grab handle, as manufactured, differs from its intended design. Plaintiff fails to even mention a manufacturing defect in its opposition, much less cite supporting materials from the record as required by Rule 56(c). To the extent plaintiff relies on a manufacturing defect theory to establish liability, no genuine dispute of material fact exists, and the court will grant defendant's request for summary judgment with respect to these claims.

IT IS THEREFORE ORDERED that defendant's motion for summary judgment be, and the same hereby is, GRANTED with respect to plaintiff's manufacturing defect claims and DENIED in all other respects.