OPINION

Marc W. Brown, Justice.

This case primarily concerns whether appellee Noble Energy, Inc.,1 owes indemnification to appellant ConocoPhillips Company for underlying environmental claims based on a 1994 Exchange Agreement and Assignment and Bill of Sale involving the exchange of oil and gas assets in Louisiana. After ConocoPhillips filed suit against Noble for declaratory judgment, and for breach of contract based on the failure to defend and indemnify and to perform other obligations, ConocoPhillips and Noble filed competing motions for summary judgment. The trial court permitted Noble to withdraw certain admissions and ultimately granted summary judgment in favor of Noble, finding as a matter of law that Noble was not a party to, did not assume and was not assigned, and otherwise had no obligation under the Exchange Agreement and assignment.

We conclude that the trial court did not abuse its discretion in permitting Noble to withdraw its admissions. However, we conclude that the Exchange Agreement constitutes an executory contract, assumed by the debtor/seller Alma Energy Corp. and assigned during chapter 11 bankruptcy proceedings and pursuant to a 2000 Asset Purchase and Sale Agreement to buyer East River Energy L.L.C./Elysium Energy, L.L.C. We also conclude that Elysium was a wholly owned subsidiary of Patina Oil & Gas Corporation and Noble Energy Production, Inc., as a wholly owned subsidiary of Noble Energy, Inc., merged with Patina. Therefore, the trial court erred in refusing to grant partial summary judgment in favor of ConocoPhillips and in granting summary judgment in favor of Noble. We reverse the trial court's final judgment, render judgment that Noble owes ConocoPhillips a duty of defense and indemnity, and remand for further proceedings.

I. FACTUAL AND PROCEDURAL BACKGROUND

The underlying lawsuit concerns alleged environmental damage to the Johnson Bayou oil and gas field in Cameron Parish, Louisiana, which has been operated as a unitized lease since approximately 1964. One of the operators of the Johnson Bayou field was General American, a predecessor to ConocoPhillips.

In 1994, Phillips Petroleum Company, another predecessor to ConocoPhillips, entered into an Exchange Agreement by which Phillips agreed to effect the transfer of certain Louisiana assets, including its interests in the Johnson Bayou field, to Alma and Texas Petroleum Investment Company (TPIC). In return, Alma and TPIC agreed to effect the transfer of certain other Louisiana assets to Phillips.

At closing, Phillips became the assignee of the Alma/TPIC leases and Alma/TPIC became the assignee of the Phillips leases, including Johnson Bayou. Under part VII of the Exchange Agreement, each assignee agreed to indemnify each assignor for all claims arising out of waste materials or hazardous substances on the exchanged leases, whether or not attributable to the assignor's actions, "prior to, during or after the period of the assignor's ownership. Each assignee also agreed to comply with laws and regulations relating to abandonment of wells or the leasehold property, and indemnify each assignor for related liabilities. Under part IX of the Exchange Agreement, each assignee agreed to indemnify each assignor for all claims, including clean-up or plugging liabilities for wells, "on account of any ... damage, destruction or loss of property, contamination of natural resources (including soil, air, surface water, or ground water) resulting from or arising out of ... or connected with the presence, disposal or release of any material of any kind ... in, under, or on the Assets," at the time of the assignment or thereafter, and whether or not caused by the assignor. All indemnities were to survive closing and the transfer of the leases.

Additionally, in the Exchange Agreement, Alma/TPIC reserved and excepted from its assignment to Phillips "a production payment equal to a net 1.15% of 8/8ths in the Lake Washington," Louisiana, leases. The "production payment" was to run for 17 years from January 1, 1994. The parties then entered into an Assignment and Bill of Sale, made subject to the Exchange Agreement. This assignment included indemnity language virtually identical to that from the Exchange Agreement. For the next five years, Alma and its operating affiliate Equinox Oil Company, Inc., operated the Johnson Bayou field. Phillips issued production payments to Alma on its retained interest in the Lake Washington leases conveyed to Phillips.

On June 10, 1999, Alma and Equinox filed for chapter 11 bankruptcy. During the bankruptcy proceeding, by auction sale, Alma and Equinox sold their assets to East River pursuant to an Asset Purchase and Sale Agreement entered into May 3, 2000. The seller companies Alma and Equinox agreed to sell and the buyer East River agreed to purchase all of the seller companies' "rights and interests in and to all contracts, agreements, purchase orders, real property, real estate leases, and personal property leases in any way associated with" the seller companies' assets, including but not limited to material contracts listed on an exhibit. East River only agreed to assume the seller companies' liability for the Assumed Liabilities and Assumed Obligations. East River's "Assumed Obligations" included "perform[ing] obligations under any executory contracts or unexpired oil and gas leases expressly assumed hereunder." These assumed obligations were to survive the closing.

The debtors' chapter 11 reorganization plan defines "Executory Contract" as "collectively, `executory contracts' and `unexpired leases' of the Debtors as of the Petition Date as such terms are used within section 365 of the Bankruptcy Code." The plan provides that all of the debtors' interests in any oil and gas leases "to the extent such leases are Executory Contracts, shall be assumed and assigned to" East River. The plan further provided that "any Executory Contract or lease not referenced above shall be assumed and assigned" to East River. The plan stated that agreements to be rejected by the debtors were listed in an exhibit to the disclosure statement. East River was to notify the debtors "of any leases or executory contracts" not listed in the exhibit that "East River elect[ed] not to have assumed and assigned to it by" the debtors. In addition, all leases or executory contracts not rejected or the subject of a motion to reject, listed on the exhibit, or on the list provided by East River to the debtors "shall be assumed by the Debtors and assigned to East River."2

The bankruptcy court approved the plan by order in August 2000. The order provided that except for contracts and agreements already assumed or rejected, "those Executory Contracts and Unexpired Leases proposed to be assumed and assigned to East River ... pursuant to the Plan are ordered assumed and assigned to East River." The order stated that executory contracts and unexpired leases proposed to be rejected pursuant to the plan and the section 365 notices are ordered rejected. The order further stated that East River has "provided adequate assurance of future performance of all Executory Contracts and Unexpired Leases being assumed and assigned to it."

After the bankruptcy court entered its order, East River changed its name to Elysium.3 Alma and Elysium then executed an Assignment, Bill of Sale and Conveyance to accomplish the transfer of interests in the oil and gas properties. This assignment incorporated the Asset Purchase and Sale Agreement and the order confirming the plan. The assignment further stated it was "made with full substitution and subrogation of [Elysium] in and to all indemnifications ... to the extent such substitution and subrogation may be made, otherwise, heretofore given or made with respect to the Interests."

In December 2003, Elysium entered into an Agreement of Purchase and Sale with Aspect Energy, LLC whereby Elysium sold its interest in the Johnson Bayou field to Aspect. Then Elysium and Azimuth Energy, LLC, a wholly owned subsidiary of Aspect, executed an Assignment and Bill of Sale to accomplish the transfer of interests.

In December 2004, Elysium's parent company Patina merged with Noble Energy Production. Under the merger, the surviving entity Noble Energy Production expressly assumed "all the obligations, duties, debts, and liabilities" of Patina.

In May 2010, the State of Louisiana and the Cameron Parish School Board filed suit in Cameron Parish district court, asserting several claims for environmental damage and contamination against ConocoPhillips and others, including Aspect and Azimuth, as current or former owners and operators of the Johnson Bayou field. ConocoPhillips made demands on both TPIC and Noble for defense and indemnity, but they each denied the demand.

In August 2011, ConocoPhillips filed suit against TPIC in Harris County district court, adding Noble as a defendant in May 2012. ConocoPhillips alleged that the defendants breached the defense and indemnity provisions in the Exchange Agreement and assignment, as well as provisions in the Exchange Agreement concerning environmental cleanup.4 ConocoPhillips reached a settlement with the school board for $63 million, which the trial court approved.5

During discovery, ConocoPhillips sent Noble requests for admission, which Noble initially answered as follows:

In August and November 2012, ConocoPhillips moved for partial6 traditional summary judgment, seeking declarations that Noble owed ConocoPhillips defense and indemnity under the Exchange Agreement. ConocoPhillips argued: the Exchange Agreement and assignment transferred ConocoPhillips' interests in the Johnson Bayou field to Alma; Alma later transferred its rights and obligations to Elysium; Noble merged with Elysium and is its successor; the underlying lawsuit includes claims of environmental damage to Johnson Bayou field; the Exchange Agreement provides that Noble owes a duty to defend ConocoPhillips from claims arising from such environmental damage; and ConocoPhillips was potentially liable to the plaintiffs in the underlying suit.

Noble responded and filed its own traditional motion for summary judgment, arguing: Elysium purchased assets and only certain liabilities during Alma's bankruptcy sale so there was no privity of contract; the bankruptcy court discharged all claims and liabilities against both Alma and Elysium; Noble has never owed an interest in or operated the property and Elysium sold its interest a year before Noble's subsidiary merged with Elysium's parent; and the claims were filed a decade after the bankruptcy and several years after Elysium sold its interests.

ConocoPhillips responded, arguing: the Exchange Agreement was an executory contract assumed by Alma and assigned to Elysium during the bankruptcy proceeding; Noble admitted that Elysium assumed both the rights and obligations from the Exchange Agreement; Noble's bankruptcy arguments fail; Noble's actions demonstrate both an express and implied assumption of the Exchange Agreement obligations; under Texas law, a corporate merger does not extinguish pre-existing contractual duties; and Noble's discharge argument contradicts 20 years of the parties' performance under and substantial reliance on the Exchange Agreement.

Noble then moved for leave to withdraw and amend its admissions 4 and 5. According to Noble, ConocoPhillips misinterpreted Noble's admissions and all Noble admitted was that "the rights and obligations in the Cameron Leases (part of the assets sold as part of the bankruptcy sale) were transferred from Alma to Elysium," as opposed to any rights or obligations from the Exchange Agreement and assignment. Noble argued that ConocoPhillips would not be unduly prejudiced because it knew about the bankruptcy and that trial was not set until June 2013.

ConocoPhillips responded that Noble failed to meet the standard for withdrawing admissions and that its request was simply a matter of legal strategy, not a mistake, and that ConocoPhillips would be unduly prejudiced and withdrawal would not serve legitimate discovery and the merits.

On December 10, 2012, the trial court7 held a hearing on Noble's motion to withdraw and amend admissions, as well as on both parties' motions for summary judgment.8 Later that same day, the trial court granted Noble's motion to withdraw and amend admissions. On December 11, Noble withdrew its admissions and replaced them with denials. Also on December 11, the trial court denied ConocoPhillips' motions for partial summary judgment. On December 31, the trial court signed an order granting Noble's motion for summary judgment. The court found "as a matter of law that Noble is not a party to, has not assumed or been assigned, and otherwise has no obligation, contractual or otherwise, under, related to, or arising out of the June 14, 1994 Exchange Agreement or the June 30, 1994 Assignment and Bill of Sale between Phillips Petroleum and Alma Energy, Inc. and Texas Petroleum Investment Company or the subject matter of those agreements."

Noble filed a motion to sever, and ConocoPhillips moved for reconsideration of the withdrawal and summary judgment decisions. The trial court9 held a hearing on March 22, 2013. The court orally agreed to permit ConocoPhillips to conduct additional discovery. The parties filed dueling motions to compel and for a status conference to vacate. The trial court10 held a hearing on May 31, 2013. In June 2013, the trial court signed an order that Noble produce a corporate representative to give testimony and documents regarding (1) tax payments made per the Exchange Agreement; (2) Noble's operations on the Johnson Bayou Field property; and (3) Noble's cleanup of the tank battery following the bankruptcy order, as well as documents "under which the business of Elysium was acquired by or merged with Noble."

In July 2013, ConocoPhillips submitted supplemental briefing and summary judgment evidence. Noble objected and moved to strike the briefing and evidence. The trial court held a hearing on August 16, 2013, on Noble's motions to strike and to sever and ConocoPhillips' motion for reconsideration. The trial court signed an order on August 28 denying ConocoPhillips' motions to reconsider the summary judgment orders. That same day, the court also granted Noble's motion to sever, stating that the court's December 31, 2012 order granting Noble's summary judgment motion was final and appealable.

ConocoPhillips timely appealed the final judgment and all interlocutory orders that merged into it. On appeal, ConocoPhillips brings four issues: whether the trial court (1) abused its discretion in permitting Noble to withdraw its express admissions; (2) otherwise erred in denying ConocoPhillips' motion for partial summary judgment where the evidence conclusively established Noble's contractual indemnity obligation; and (3) erred in granting Noble's motion for summary judgment because ConocoPhillips conclusively proved that Noble's obligations were not discharged in bankruptcy or (4) where the evidence created a fact issue on the same.

II. ANALYSIS

A. The trial court did not abuse its discretion in allowing Noble to withdraw its admissions.

ConocoPhillips contends that the trial court abused its discretion in permitting Noble to withdraw its admissions 4 and 5. We disagree.

A party may withdraw or amend an admission if: (a) the party shows good cause for the withdrawal or amendment, and (b) the court finds that the parties relying upon the responses and deemed admissions will not be unduly prejudiced and that the presentation of the merits of the action will be subserved by permitting the party to amend or withdraw the admission. Tex. R. Civ. P. 198.3. "Good cause is established by showing that the failure involved was an accident or mistake, not intentional or the result of conscious indifference." Wheeler v. Green, 157 S.W.3d 439, 442 (Tex.2005) (per curiam). A trial court has broad discretion to permit or deny the withdrawal of admissions. See Stelly v. Papania, 927 S.W.2d 620, 622 (Tex.1996) (per curiam). We only set aside the trial court's ruling if, after reviewing the entire record, it is clear that the court abused its discretion. Id.

ConocoPhillips argues that Noble did not establish good cause because its admissions were not the result of mistake or inadvertence11 where Noble made the same admissions consistently in letters to its insurer and in a counterclaim filed against its insurer, and cannot establish good cause by asserting it did not realize the implications of its admissions. In addition, ConocoPhillips argues that it was unduly prejudiced by the belated withdrawal and that the belated order permitting discovery did not cure such prejudice.12

Noble insists that the requested admissions are irrelevant because they involved legal questions as opposed to facts under rule 198.1.13 Further, Noble contends its admissions 4 and 514 were the result of an accident or mistake in that Noble only intended to admit that certain rights and obligations in the Johnson Bayou field were transferred through bankruptcy from Alma to Elysium, and once it realized ConocoPhillips' interpretation was different, i.e., that Noble was admitting "Elysium assumed all obligations under the Exchange Agreement and the Assignment," it promptly emailed counsel about the mistake15 and then timely moved to amend. Noble also argues that its withdrawal did not delay trial or significantly hamper ConocoPhillips' ability to prepare.

Keeping in mind that that "[t]he primary purpose of requests for admission is to simplify trials by eliminating matters about which there is no real controversy," Peralta v. Durham, 133 S.W.3d 339, 341 (Tex.App.-Dallas 2004, no pet.)16; that whether and what, if any, obligations Elysium had assumed from Alma stemming from the Exchange Agreement was in dispute; and that "[e]ven a slight excuse will suffice, especially where delay or prejudice will not result against the opposing party," Kheir v. Progressive Cnty. Mut. Ins. Co., No. 14-04-00694-CV, 2006 WL 1594031, at *5 (Tex.App.-Houston [14th Dist.] June 13, 2006, pet. denied) (mem.op.), we cannot conclude that the trial court committed a clear abuse of discretion by permitting Noble to withdraw its admissions.

We overrule ConocoPhillips' first issue.

B. The trial court's summary judgment decisions

Because the remaining issues all relate to the trial court's decisions to grant summary judgment in favor of Noble and against ConocoPhillips, we consider them together.

1. Standard of review

When both parties move for summary judgment and a trial court grants one motion and denies the other, as here, we consider both sides' summary-judgment evidence, determine de novo all issues, and render the judgment the trial court should have rendered. See Gilbert Tex. Const., L.P. v. Underwriters at Lloyd's London, 327 S.W.3d 118, 124 (Tex. 2010) (subs.op.); NuStar Energy, L.P. v. Diamond Offshore Co., 402 S.W.3d 461, 465 (Tex.App.-Houston [14th Dist.] 2013, no pet.). The movant is entitled to summary judgment when it demonstrates that no genuine issues of material facts exist and that it is entitled to judgment as a matter of law. Tex. R. Civ. P. 166a(c); Mann Frankfort Stein & Lipp Advisors, Inc. v. Fielding, 289 S.W.3d 844, 848 (Tex. 2009). Evidence is conclusive if reasonable people could not differ in their conclusions. City of Keller v. Wilson, 168 S.W.3d 802, 816 (Tex.2005). When deciding whether a fact issue exists, we accept all evidence favorable to the nonmovant and resolve any doubts in its favor. Valence Operating Co. v. Dorsett, 164 S.W.3d 656, 661 (Tex.2005); Burroughs v. APS Int'l, Ltd., 93 S.W.3d 155, 159 (Tex.App.-Houston [14th Dist.] 2002, pet. denied).

2. Contract interpretation

The construction of an unambiguous contract presents a question of law subject to de novo review. Tawes v. Barnes, 340 S.W.3d 419, 425 (Tex.2011); Washington Square Fin., LLC v. RSL Funding, LLC, 418 S.W.3d 761, 767 (Tex. App.-Houston [14th Dist.] 2013, pet. denied). Our primary concern in interpreting a contract is to ascertain and to give effect to the intentions of the parties as expressed in the instrument. J.M. Davidson, Inc. v. Webster, 128 S.W.3d 223, 229 (Tex.2003). We therefore give terms their plain and ordinary meaning unless the contract indicates that the parties intended a different meaning. Dynegy Midstream Servs., Ltd. P'ship v. Apache Corp., 294 S.W.3d 164, 168 (Tex.2009). We construe indemnity agreements under normal rules of contract construction. Gulf Ins. Co. v. Burns Motors, Inc., 22 S.W.3d 417, 423 (Tex.2000). We examine and consider the entire writing in an effort to harmonize and give effect to all provisions of the contract, so that none will be rendered meaningless. J.M. Davidson, 128 S.W.3d at 229.

Whether a contract is ambiguous is a legal question for courts to decide. Gulf Ins., 22 S.W.3d at 423; see Coker v. Coker, 650 S.W.2d 391, 394 (Tex.1983). "A contract is ambiguous when its meaning is uncertain and doubtful or is reasonably susceptible to more than one interpretation." Heritage Res., Inc. v. NationsBank, 939 S.W.2d 118, 121 (Tex.1996). A contract is not ambiguous simply because the parties advance conflicting interpretations. Columbia Gas Transmission Corp. v. New Ulm Gas, Ltd., 940 S.W.2d 587, 589 (Tex.1996). If the contract is subject to more than one reasonable interpretation after applying the pertinent rules of contract construction, then the contract is ambiguous and there is a fact issue regarding the parties' intent. El Paso Field Servs., L.P. v. MasTec N. Am., Inc., 389 S.W.3d 802, 806 (Tex.2012); J.M. Davidson, 128 S.W.3d at 229. Here, neither party argues that the contracts at issue are ambiguous — each simply insists its respective interpretation is the correct one.

C. The parties' competing positions on summary judgment

1. The Asset Purchase and Sale Agreement

ConocoPhillips argues that even without Noble's admissions, it presented conclusive proof of Noble's duty to defend/indemnify. According to ConocoPhillips, uncontroverted evidence shows Noble merged with Elysium and assumed all of Elysium's contractual obligations, which included the Exchange Agreement's indemnity obligation. ConocoPhillips asserts the record conclusively establishes that Elysium purchased the Exchange Agreement from Alma's bankruptcy estate in 2000.

Under section 1.01(d) of the Asset Purchase and Sale Agreement, Elysium agreed to purchase:

ConocoPhillips asserts that the Exchange Agreement is a contract "associated" with the Johnson Bayou field Asset falling within section 1.01(d). ConocoPhillips points out that the Asset Purchase and Sale Agreement did not exclude contracts involving vested assets and did not otherwise include the Exchange Agreement as an Excluded Asset in section 1.0218 of the Asset Purchase and Sale Agreement. ConocoPhillips further argues that it would not make sense for Elysium to be able to assume rights but not obligations under the contracts it was purchasing.

Noble responds that ConocoPhillips is wrong when it asserts that Elysium assumed the Exchange Agreement with Alma's liabilities. Although it maintains Elysium was not assigned the Exchange Agreement at all under the Asset Purchase and Sale Agreement, Noble contends that even if a party's rights under a contract are assigned, the assignee is not obligated to perform the assignor's obligations unless it expressly assumes them. Noble further insists that the plain language of the Asset Purchase and Sale Agreement is inconsistent with the interpretation that Elysium assumed Alma's obligations from the Exchange Agreement.

To the extent Noble argues a purchaser of assets does not necessarily automatically assume liabilities and obligations of the seller, we generally agree that may be the case in certain successor-liability contexts.19 Moreover, in the context of assignment of a contract, the assignee only can be held liable under the predecessor's contract if the assignee expressly or impliedly assumes the predecessor's contractual obligations. See Jones v. Cooper Indus., Inc., 938 S.W.2d 118, 125-26 (Tex.App.-Houston [14th Dist.] 1996, writ denied); see also NextEra Retail of Tex., LP v. Investors Warranty of Am., Inc., 418 S.W.3d 222, 226-27 (Tex.App.-Houston [1st Dist.] 2013, pet. denied) (discussing Jones).

Under the plain language of the Asset Purchase and Sale Agreement, presuming that the Exchange Agreement does fall within Elysium's agreement to purchase "rights and interests in and to all contracts" in section 1.01(d), this does not automatically mean Elysium also agreed to purchase all obligations and liabilities contained within the Exchange Agreement. This is particularly the case where the Asset Purchase and Sale Agreement in sections 1.0420 and 8.0321 includes express provisions detailing what Assumed Liabilities and Assumed Obligations Elysium was agreeing to assume. Further, section 1.06, Liabilities, of the Asset Purchase and Sale Agreement provides:

Inclusion of this section is consistent with the interpretation that a certain limited set of liabilities and obligations would be transferred to Elysium as part of the bankruptcy proceedings, pursuant to the Asset Purchase and Sale Agreement. Therefore, we cannot find summary judgment in favor of ConocoPhillips on the basis that section 1.01(d) acted to transfer both Alma's rights and obligations in the Exchange Agreement to Elysium.

2. Whether the Exchange Agreement was assumed and assigned as an executory contract

We must also determine whether the Exchange Agreement's obligations otherwise were expressly assumed by Elysium within the Asset Purchase and Sale Agreement. In making this determination, we remain mindful that the sale took place within the bankruptcy context. Therefore, we must determine whether the Exchange Agreement is an executory contract, whether Alma assumed the Exchange Agreement under section 365, and then whether it assigned its rights and obligations to Elysium. See 11 U.S.C. § 365(f)(2)(A) (2013); Bonneville Power Admin. v. Mirant Corp. (In re Mirant Corp.), 440 F.3d 238, 253 (5th Cir.2006) ("According to § 365(f)(2)(A), assumption must precede assignment."); Compton v. Mustang Eng'g Ltd. (In re MPF Holding U.S. L.L.C.), 495 B.R. 303, 321 (Bankr. S.D.Tex.2013) ("[S]ection 365 is the exclusive provision for dealing with executory contracts in bankruptcy.").

ConocoPhillips argues that under article X of the bankruptcy plan, executory contracts such as the Exchange Agreement were expressly assumed and assigned to Elysium. Sections 10.8 and 10.9 of the plan provide:

ConocoPhillips asserts that the Exchange Agreement was not rejected or subject to a rejection motion as of the date of the confirmation hearing, was not listed in a particular exhibit to the disclosure statement, and was not expressly rejected by Elysium by the contract election date.

Based on the plain language of the plan,22 we agree that the plan indicates that Alma was expressly assuming all executory contracts not otherwise rejected pursuant to a motion to reject, rejected as expressly listed by Alma in the disclosure statement, or rejected on the list as provided by Elysium. We also agree that the record here reflects that the Exchange Agreement was not the subject of a rejection motion, was not disclosed in exhibit J of the disclosure statement, and was not listed on Elysium's listing of executory contracts for rejection. We further note the bankruptcy court's confirmation order, paragraph 15, is consistent with this interpretation, providing that except for contracts and agreements already assumed or rejected, "those Executory Contracts and Unexpired Leases proposed to be assumed and assigned to [Elysium] ... pursuant to the Plan are ordered assumed and assigned to [Elysium]." The order stated that executory contracts and unexpired leases proposed to be rejected pursuant to the plan and the section 365 notices are ordered rejected. The order also stated that Elysium has "provided adequate assurance of future performance of all Executory Contracts and Unexpired Leases being assumed and assigned to it."

Noble contends that ConocoPhillips relies too heavily on the plan and insists that the Asset Purchase and Sale Agreement provides a different interpretation relating to assumption by Alma and assignment to Elysium. However, our review of the plain language of the Asset Purchase and Sale Agreement is consistent with the plan's language that Alma would assume all remaining executory contracts and leases and assign them to Elysium. Within the agreement in section 8.03(b), Elysium agreed that post-closing it "shall have" the following "Assumed Obligation" — to "perform obligations under any executory contracts or unexpired oil and gas leases expressly assumed hereunder." The Asset Purchase and Sale Agreement included section 1.03, which described the bankruptcy plan as "incorporating the terms and conditions as set forth in this Agreement," and article VI included conditions to closing, which stated that the plan "materially conforms to the terms and conditions of this Agreement" and that "this Agreement shall specifically be approved by the Bankruptcy Court and shall be incorporated as part of the Plan." In section 8.04(b), Alma agreed to be responsible post-closing for all claims and liabilities with respect to the assets accruing or relating to the times prior to the effective time, essentially the morning of closing, "[e]xcept for those matters expressly assumed by [Elysium]." And under section 8.09, the provisions of article VIII, including Elysium's assumed obligations, "shall survive the Closing."

Moreover, the indemnification provisions of the Asset Purchase and Sale Agreement can be harmonized with the interpretation that Alma assumed and assigned all remaining executory contracts to Elysium. Both Elysium and Alma in sections 8.05 and 8.06 agreed to indemnify the other from and against claims arising from or attributable to their respective periods of ownership and operation of the assets and any breaches of their respective "representations, warranties, covenants, or agreements hereunder." However, under section 8.05, Indemnification by Buyer, in addition, Elysium agreed to indemnify Alma from and against all claims arising from or attributable to "THE ASSUMED OBLIGATIONS." Therefore, we cannot agree with Noble that ConocoPhillips' interpretation of the Asset Purchase and Sale Agreement renders sections 8.04(b) and 8.06 meaningless.23

Having concluded the plain language of the Asset Purchase and Sale Agreement, and of the plan and the order, aligns with ConocoPhillips' interpretation that Alma assumed remaining executory contracts and any such executory contracts were assigned to Elysium as "assumed obligations," we proceed to determine whether the Exchange Agreement constitutes an executory contract within section 365 of the bankruptcy code. Based on our review of the governing law and of the agreement, we conclude that the answer is yes.

According to ConocoPhillips, the unperformed, remaining mutual indemnity obligations rendered the Exchange Agreement executory for the purposes of section 365 of the bankruptcy code. In addition, ConocoPhillips insists the Exchange Agreement "contained many more remaining obligations than just the mutual indemnification obligations."24 ConocoPhillips primarily relies on In re Safety-Kleen Corp., 410 B.R. 164, 167-68 (Bankr.D.Del. 2009), wherein the bankruptcy court concluded that a stock purchase agreement involving some unperformed, remaining mutual indemnification obligations relating to certain environmental matters was an executory contract. See also Philip Servs. Corp. v. Luntz (In re Philip Servs. (Del.), Inc.), 284 B.R. 541, 548-50 (Bankr.D.Del. 2002) (merger agreement imposed similar unperformed indemnification obligations on both parties, as well as remaining non-monetary obligations, and was executory).25

In contrast, Noble takes the position that the Exchange Agreement was not an executory contract.26 First, Noble points to cases indicating that contracts where the only remaining performance is monetary in nature are not executory, and where the courts have found contracts containing a continuing indemnification obligation nonexecutory. See, e.g., In re Farmland Indus., Inc., 318 B.R. 159, 163 (Bankr.W.D.Mo.2004); In re Spectrum Info. Technologies, Inc., 190 B.R. 741, 748 (Bankr.E.D.N.Y.1996); In re Chateaugay Corp., 102 B.R. 335, 347 (Bankr.S.D.N.Y. 1989). Noble argues that, as in these cases, the Exchange Agreement was fully consummated and performed, except for future, contingent environmental liabilities.27

Pursuant to section 365, subject to the bankruptcy court's approval, any executory contract of the debtor may be assumed or rejected. 11 U.S.C. § 365(a) (2013); see Century Indem. Co. v. Nat'l Gypsum Co. Settlement Trust (In re Nat'l Gypsum Co.), 208 F.3d 498, 504 (5th Cir.2000) ("Under § 365, a debtor may elect one of two options when assessing how to treat an executory contract or unexpired lease to which it is a party; the contract or lease may either be rejected or assumed.").28 This provision allows a trustee to relieve the bankruptcy estate of a burdensome agreement that has not been completely performed. Phoenix Exploration, Inc. v. Yaquinto (In re Murexco Petroleum, Inc.), 15 F.3d 60, 62 (5th Cir.1994) (per curiam). The decision whether to assume or reject under section 365 is generally left to the business judgment of the bankruptcy estate. See Mirant Corp. v. Potomac Electric Power Co. (In re Mirant Corp.), 378 F.3d 511, 524 n. 5 (5th Cir.2004).

Although the bankruptcy code does not define "executory contract," "[c]ourts applying § 365(a) have indicated that an agreement is executory if at the time of the bankruptcy filing, the failure of either party to complete performance would constitute a material breach of the contract, thereby excusing the performance of the other party." Murexco Petroleum, 15 F.3d at 62-63 & n. 8 (noting that source of this definition "is a two-part article by Professor Vern Countryman, Executory Contracts in Bankruptcy: Part I, 57 Minn. L.Rev. 439, 458-62 (1973), and Executory Contracts in Bankruptcy: Part II, 57 Minn. L.Rev. 479 (1974)"); see Potomac Electric, 378 F.3d at 518 n. 3 ("Section 365(a) does not define executory contract, but the legislative history of that section indicates that the term means a contract `on which performance is due to some extent on both sides.'").29 "Whether an obligation is material is tested at the time of the filing of the bankruptcy petition." Safety-Kleen, 410 B.R. at 167; see Murexco Petroleum, 15 F.3d at 62. Therefore, to determine if the Exchange Agreement was executory at the time that Alma filed its bankruptcy petition, we must consider whether Alma and Phillips had duties the nonperformance of which would have constituted a material breach of the Exchange Agreement at the time of the filing of the petition. See Murexco Petroleum, 15 F.3d at 62-63.

Contingent material obligations are sufficient to render a contract executory. Safety-Kleen, 410 B.R. at 168. That is, a contingent material obligation, even though not yet triggered on a debtor's petition date, is nevertheless executory until expiration of the contingency because "[u]ntil the time has expired during which an event triggering a contingent duty may occur, the contingent obligation represents a continuing duty to stand ready to perform if the contingency occurs." Richmond Metal, 756 F.2d at 1046. Further, it is well-settled that an executory contract cannot be assumed in part and rejected in part. Stewart Title Guar. Co. v. Old Republic Nat'l Title Ins. Co., 83 F.3d 735, 741 (5th Cir.1996) (per curiam). That is, "[w]here the debtor assumes an executory contract, it must assume the entire contract, cum onere — the debtor accepts both the obligations and the benefits of the executory contract." Century Indem., 208 F.3d at 506.

We find Safety-Kleen and Philip Services, bankruptcy court opinions which both applied the Countryman definition of executory contract, to be particularly instructive. The Safety-Kleen court considered the pertinent indemnity section of the stock purchase contract at issue, which provided that "subject to a certain dollar limit, Westinghouse and Rollins each held contingent, unliquidated rights of indemnification against the other with respect to any and all damages arising from pre-and-post-closing environmental matters, including contamination relating to the Coffeyville Facility." 410 B.R. at 166. After acknowledging that "a contract is executory if both parties have unperformed obligations that, if not completed, would result in a material breach," id. at 167, and considering that "[c]ourts have ruled that contingent obligations under a contract are sufficient to render a contract executory when the contingent obligations are essential to the contract," id. at 168, the court concluded that the indemnity provisions of the stock purchase agreement at issue were material and the agreement was an executory contract at the time of the debtors' filing for bankruptcy, id. at 169-70. In doing so, the Safety-Kleen court noted how the indemnity provisions provided benefits and burdens to both parties that continued at the time of the debtors' filing for bankruptcy: "Stated succinctly, the indemnity provisions were not nullities." Id. at 169.

Likewise, in Philip Services, the bankruptcy court considered whether a merger agreement was executory for purposes of section 365. 284 B.R. at 547. The dispute centered over whether additional material obligations remained due from both parties. Id. In concluding that the contract was executory, the bankruptcy court considered that one party remained obligated to perform environmental remediation duties associated with the properties and that the other party remained obligated for ongoing environmental compliance at certain contaminated sites. Id. at 547-48. In addition, under the agreement, there were similar, continuing, largely unperformed indemnification obligations remaining as to both parties. Id. at 548-49. The court rejected the argument that the merger agreement was "not an executory contract because the unperformed indemnification obligations are not material," distinguishing Chateaugay Corp. and similar cases "where one party has completed performance, ... or where the only performance that remains is the payment of money." Philip Servs., 284 B.R. at 549 (quoting Chateaugay Corp., 102 B.R. at 348) (emphasis omitted). In contrast to such cases, the court noted how "neither side has completed performance and both sides have monetary and non-monetary obligations remaining." Id. at 549. Although the court acknowledged that the merger agreement had a principal purpose of the sale of the corporation and its assets, it concluded that the future mutual obligations, including "the promise to indemnify," were "substantial element[s] of the overall transaction." Id. at 550 (discussing Waldschmidt v. Metro. Lincoln-Mercury, Inc. (In re Preston), 53 B.R. 589, 591 (Bankr.M.D.Tenn.1985)); see also In re AbitibiBowater Inc., 418 B.R. 815, 831 (Bankr.D.Del.2009) (citing Safety-Kleen, 410 B.R. at 168, and Philip Servs., 284 B.R. at 549-50, and concluding that mutual continuing indemnity obligations for environmental damage caused by mill operation were material and call agreement containing them was executory).

Unlike the cases cited by Noble,30 the Exchange Agreement here contains continuing, mutual, future, largely unperformed, material obligations, both monetary and nonmonetary in nature. Both Alma and Phillips respectively agreed to defend and indemnify the other from and against all claims caused by or arising out of the presence, disposal, release, or threatened release of hazardous substances or waste before, during, or after ownership of the exchanged assets, and to defend and indemnify the other from and against all claims, including contamination of natural resources, resulting from or arising out of any liability caused by or connected with the presence, disposal, or release of any material in, under, or on the exchanged assets at the time of or after assignment. We take particular note of the reciprocal, mutual nature of these indemnity obligations. See Wilson v. TXO Prod. Corp. (In re Wilson), 69 B.R. 960, 962 (Bankr.N.D.Tex.1987) (noting how legislative history adopts "principle of mutuality" and holding operating agreements where both parties have continuing obligations were executory); see also In re RoomStore, Inc., 473 B.R. 107, 115 (Bankr. E.D.Va.2012) ("The dispositive distinction is that in this case there was a continuing obligation on each side."). Further, the Exchange Agreement expressly provides that these mutual indemnification obligations indefinitely survive closing and the transfer of the assets; in fact, the parties considered the indemnification obligations to be of such importance that, as noted above, they included these obligations in the assignment conveying the respective leases.

Moreover, both Alma and Phillips mutually agreed to take all future environmental disposal, cleanup, and remedial actions related to their respective exchanged assets. And, although we acknowledge the Exchange Agreement indicated within its recitals its purposes for Alma and Phillips to effect the transfer of their respective assets, we nonetheless conclude that the remaining mutual indemnification obligations, along with mutual responsibilities regarding environmental cleanup, constituted material obligations. See Safety-Kleen, 410 B.R. at 167-70; Philip Servs., 284 B.R. at 549-50. These obligations were detailed in several places in the Exchange Agreement and were largely carried over into the Assignment and Bill of Sale conveying the property to Alma.31

In sum, at the time of the filing of the bankruptcy petition, the failure of either Alma or Phillips to complete performance of its mutual obligations would have constituted a material breach of the Exchange Agreement. See Murexco Petroleum, 15 F.3d at 62-63. Therefore, we conclude that the Exchange Agreement is an executory contract for purposes of section 365.

3. No remaining fact issues32

Having concluded that Alma assumed, and Elysium was assigned, the Exchange Agreement as an executory contract as part of the bankruptcy proceedings whereby Elysium purchased the assets of Alma through a bankruptcy order and plan confirming the Asset Purchase and Sale Agreement, we consider whether ConocoPhillips conclusively established Noble assumed all the rights and obligations of Patina as a matter of law.

In its brief, Noble acknowledges that "the link between Elysium and Noble" is "not materially in dispute" and "agrees that it is Elysium's successor for the purposes of this appeal." Nevertheless, despite Noble's withdrawn merger admission, and even without having to consider the propriety of whether to consider any evidence gathered and supplemented after the trial court rendered summary judgment, our review of the record evidence at the time of summary judgment submission confirms this fact. Therefore, we conclude that ConocoPhillips conclusively established as of December 15, 2004, Noble effected a merger with Patina, of which Elysium was a wholly-owned subsidiary, whereby "all the obligations, duties, debts and liabilities of [Patina] and [Noble Energy Production] shall be the obligations, duties, debts and liabilities of the Surviving Corporation" — Noble Energy Production — as expressly and plainly stated within the Agreement and Plan of Merger executed by Patina, Noble Energy, and Noble Energy Production.

We sustain ConocoPhillips' second and third issues.33

III. CONCLUSION

In light of the foregoing, we conclude that the trial court did not abuse its discretion in permitting Noble to withdraw its admissions 4 and 5. However, we conclude the trial court erred in its denial of ConocoPhillips' partial traditional motions for summary judgment and in its granting of Noble's motion for summary judgment. We therefore reverse the trial court's final judgment, render judgment that Noble owes ConocoPhillips a duty of defense and indemnity, and remand for additional proceedings consistent with this opinion.