Lease Reformation for Mutual Mistake Extinguishes Option-Based Claims, While Co-Venturer Fiduciary Duties May Survive a Business Fallout

Case: Laun v Stewart, 2026 NY Slip Op 01883 (App Div, 4th Dept Mar. 27, 2026)
Court: Appellate Division of the Supreme Court, New York, Fourth Department
Disposition: Order modified; reformation granted; several claims dismissed on summary judgment; fiduciary-duty claim(s) against co-venturers/members preserved due to fact issues.

1. Introduction

Laun v Stewart arises from a deteriorated marina leased with an option to purchase. Plaintiff Eugene Laun, Jr. sued the lessor/owner John Stewart and his former business counterparts Robert and Donna Stivers after the Stivers defendants purchased the marina shortly after the lease-option period expired.

The core dispute turned on a drafting mismatch: the written lease, drafted by Stivers, contained a one-year term plus an option to renew annually for five additional one-year periods—text that, on its face, implied a six-year total. All parties, however, later testified that they intended a total of five years. The timing mattered because the option was not exercised before the lease-option period ended; after expiration, Stewart sold to the Stivers defendants.

The appeal and cross-appeals focused on three clusters of issues:

  • Reformation: whether the lease should be reformed to reflect a five-year total term (mutual mistake).
  • Option-related liability: whether Stewart breached the covenant of good faith and fair dealing or aided and abetted fiduciary breaches by entertaining a post-expiration sale.
  • Fiduciary duties among the business participants: whether the Stivers defendants owed fiduciary duties as joint venturers or LLC members, and whether those duties were still in force when they bought the marina.

2. Summary of the Opinion

The Fourth Department modified Supreme Court’s order (which had denied all summary judgment motions) and held:

  • Lease reformation granted: Defendants established entitlement to reformation of the lease to a total five-year period (including renewals), because the writing did not reflect the parties’ actual agreement due to mutual mistake/scrivener’s error.
  • Option-based claims dismissed on summary judgment: With the lease reformed and the option not timely exercised, the court granted summary judgment dismissing:
    • Against Stewart: the first (breach of contract), third (breach of covenant of good faith and fair dealing), fifth (determination of claims to real property), sixth (cancellation of deed), and eighteenth (aiding and abetting breach of fiduciary duty) causes of action.
    • Against the Stivers defendants: the fourth (tortious interference with contract), fifth, and sixth causes of action.
  • Fiduciary-duty claim against the Stivers defendants survived: Neither side obtained summary judgment on the seventeenth cause of action (breach of fiduciary duty). The court found triable issues, including whether a joint venture (or LLC-related fiduciary relationship) persisted through the purchase and whether it was terminated.

3. Analysis

3.1. Precedents Cited

A. Reformation: presumption of correctness, mutual mistake, and admissibility of proof

  • George Backer Mgt. Corp. v Acme Quilting Co. (46 NY2d 211 [1978]) anchored the “heavy presumption” that a deliberately prepared written instrument reflects the parties’ true intent, and that overcoming that presumption demands strong proof. The Fourth Department invoked this presumption as the baseline, then explained why the record satisfied the higher evidentiary burden.
  • Chimart Assoc. v Paul (66 NY2d 570 [1986]) supplied the modern reformation framework: reformation is available where mutual mistake (or fraud) causes a writing to deviate from the parties’ agreement. It also supported the point that, because the claim asserts the writing is wrong, the parol evidence rule and Statute of Frauds generally do not bar proof.
  • Harris v Uhlendorf (24 NY2d 463 [1969]) provided the key distinction the court applied: where the mistake is not about the agreement itself but about reducing that agreement to writing (scrivener’s error), reformation may correct it “no matter how it occurred.”
  • Stache Invs. Corp. v Ciolek (174 AD3d 1393 [4th Dept 2019]) was cited consistently with Chimart Assoc. and Harris for mutual mistake principles and the evidentiary pathway to prove the parties’ real agreement.
  • Vega v Restani Constr. Corp. (18 NY3d 499 [2012]) supplied the summary judgment lens: evidence must be viewed in the light most favorable to the nonmoving party. The court used Vega in rejecting plaintiff’s attempt to manufacture a triable issue from post-execution statements.

B. Covenant of good faith and fair dealing: protecting “fruits of the contract” without creating new rights

  • 511 W. 232nd Owners Corp. v Jennifer Realty Co. (98 NY2d 144 [2002]) and Dalton v Educational Testing Serv. (87 NY2d 384 [1995]) provided the doctrinal statement that every contract implies a covenant of good faith and fair dealing, including the classic rule that neither party may act to destroy or injure the other’s right to receive the contract’s benefits.
  • Paramax Corp. v VoIP Supply , LLC (175 AD3d 939 [4th Dept 2019]) reinforced the Fourth Department’s own application of the covenant and framed the analysis of whether the defendant’s conduct actually interfered with contractual benefits.

C. Fiduciary duty, joint ventures, and termination questions

  • Golobe v Mielnicki (44 NY3d 86 [2025], rearg denied 43 NY3d 1013 [2025]) supplied the elements of a fiduciary-duty claim: (1) fiduciary relationship, (2) misconduct, (3) damages caused by misconduct. The Fourth Department used this to explain why summary judgment was inappropriate given unresolved questions about relationship status and conduct.
  • Oddo Asset Mgt. v Barclays Bank PLC (19 NY3d 584 [2012], rearg denied 19 NY3d 1065 [2012]) provided the general definition of a fiduciary relationship: a duty to act for or advise another within the scope of the relationship.
  • IPA Asset Mgt. , LLC v Schuman (239 AD3d 619 [2d Dept 2025]) was central to the joint-venture analysis, supplying: the definition of a joint venture, the “essential elements” (including joint control and sharing of profits and losses), and the rule that an agreement may be oral and inferred from conduct. The Fourth Department applied this to hold that, even if not labeled a joint venture in the pleading, plaintiff alleged facts from which one could be inferred.
  • Alper Rest. , Inc. v Catamount Dev. Corp. (137 AD3d 1559 [3d Dept 2016]) and Richbell Info. Servs. v Jupiter Partners (309 AD2d 288 [1st Dept 2003]) reinforced the joint-venture element set the court recited.
  • Weisman v Awnair Corp. of Am. (3 NY2d 444 [1957]) and Rutecki v Gow & Co. (289 AD2d 1066 [4th Dept 2001]) grounded the general rule that absent a written duration term, a joint venture is terminable at will.
  • Hooker Chems. & Plastics Corp. v International Mins. & Chem. Corp. (90 AD2d 991 [4th Dept 1982]) supplied the crucial qualification: where the venture’s object is completing specified work or achieving a specified result, it is presumed to continue until the object is accomplished—and whether it is at-will or objective-based is a question of fact.
  • Meinhard v Salmon (249 NY 458 [1928]) and Mendelovitz v Cohen (66 AD3d 849 [2d Dept 2009]) were cited in support of the “specified result” presumption and the durability of fiduciary principles in joint enterprise settings.
  • The court also cited South Shore Eye Care , LLP v Lane (242 AD3d 792 [2d Dept 2025]), Cohen & Lombardo , P.C. v Connors (169 AD3d 1399 [4th Dept 2019]), and McGuire v Huntress [appeal No. 2] (83 AD3d 1418 [4th Dept 2011], lv denied 17 NY3d 712 [2011]) as supporting authority for fiduciary-duty elements and application.

3.2. Legal Reasoning

A. Why reformation was granted despite the “heavy presumption” favoring the writing

The lease’s text created an objective inconsistency: a one-year term plus “five (5) separate, annual one (1) year periods” reads as six total years. Yet the court treated the problem as classic mutual mistake/scrivener’s error. The decisive proof was uniform: Stewart, plaintiff, and the Stivers defendants all testified or averred that at execution they intended a total five-year lease term.

Plaintiff tried to defeat reformation by pointing to his claimed post-signing conversation where Stivers allegedly called the extra year “our ace in the hole” and suggested not telling Stewart. Even assuming plaintiff’s version, the court held it showed (at most) that Stivers learned of the error after execution. That did not create a triable issue that the parties’ intent at signing was a six-year term. The court also emphasized the lack of post-execution conduct consistent with a six-year belief, noting the parties’ urgency near the five-year mark to address the option deadline.

Key doctrinal move: the court separated (i) what the parties agreed to, from (ii) what the document mistakenly said—placing the case squarely within the Harris v Uhlendorf line that permits correction where the only mistake is the reduction to writing.

B. How reformation drove dismissal of the option-centered claims

Once the lease was reformed to a five-year total, the option necessarily expired earlier than plaintiff urged. Because the option was not exercised by the deadline, plaintiff’s claims premised on an enforceable option right—contract breach against Stewart, tortious interference against the Stivers defendants, and equitable/real property theories (determination of claims to real property; cancellation of the deed)—could not survive summary judgment on this record.

Although the opinion does not re-litigate each element of each dismissed claim at length, the structure of the ruling makes the logic plain: without a timely exercised option (and without a longer option period), there is no contractual purchase right to vindicate and no basis to unwind the later conveyance on the theories pleaded.

C. Why the covenant of good faith and fair dealing claim failed (and why the aiding-and-abetting claim against Stewart fell with it)

Plaintiff’s theory was that Stewart breached the covenant—and aided and abetted fiduciary breach—by agreeing before the deadline to sell to the Stivers defendants after the deadline. The court rejected that characterization based on Stewart’s evidence:

  • the parties’ relationship fractured well before the deadline, and both sides separately sought to exercise the option without the other;
  • Stewart would not permit unilateral exercise; and
  • he sold only after the lease/option expired.

Under 511 W. 232nd Owners Corp. v Jennifer Realty Co. and Dalton v Educational Testing Serv., the covenant polices conduct that injures the counterparty’s receipt of contractual benefits. On these facts, the court found no “hindering” of a joint exercise of the option and no pre-expiration agreement that undermined plaintiff’s ability to pursue the contract’s benefits. Stewart’s statements that he would “consider” a sale if terms were similar did not amount to a binding deal that sabotaged plaintiff’s contract rights.

D. Why the fiduciary-duty claim against the Stivers defendants could not be resolved on summary judgment

The fiduciary-duty dispute turned on relationship status and timing: did the Stivers defendants still owe plaintiff fiduciary obligations when they chose not to exercise the option with him and then purchased the marina after expiration?

The court held there were triable issues whether plaintiff and the Stivers defendants were joint venturers (or whether fiduciary duties existed through LLC membership), and whether that relationship had been terminated. Importantly, the court rejected a simplistic “falling out equals termination” approach:

  • Under Weisman v Awnair Corp. of Am. and Rutecki v Gow & Co., an unwritten-duration joint venture is generally at-will.
  • Under Hooker Chems. & Plastics Corp. v International Mins. & Chem. Corp. (with support from Meinhard v Salmon), if the venture’s object is achieving a specified result, the relationship is presumed to continue until that objective is accomplished.
  • Whether the venture was at-will or objective-bound—and whether it (or the LLC) was terminated at the relevant time—was deemed a fact question.

Thus, the case proceeds (at least) on whether fiduciary duties existed and were breached by “excluding” plaintiff from the acquisition opportunity, and whether any damages flowed directly from that alleged misconduct under Golobe v Mielnicki.

3.3. Impact

A. Drafting errors in option/term provisions: reformation can be decisive and case-dispositive

The opinion underscores that even a seemingly “plain” textual reading (here, six years) can yield to reformation where the evidentiary record is unified and shows the writing failed to capture the agreed term. In commercial real estate disputes, this can abruptly reframe: option deadlines, default claims, interference allegations, and deed-based remedies.

B. Covenant of good faith limits in post-expiration sale contexts

Laun v Stewart signals that a landlord/optionor may avoid covenant liability where the optionor: (i) refuses unilateral exercise inconsistent with the option’s structure, (ii) does not bind itself to a pre-expiration side deal, and (iii) sells only after expiration. The covenant protects contractual fruits; it does not resurrect expired options or impose a duty to extend deadlines.

C. Continuing fiduciary exposure among co-operators, even after personal breakdown

For closely held ventures and LLC-based projects, the decision is a warning that fiduciary duties may persist despite a “falling out,” especially if a factfinder could infer the enterprise had a defined objective (e.g., acquiring and operating the marina) not yet accomplished. The termination question—often assumed—may be litigated, and the acquisition of a core asset by one faction can remain vulnerable to fiduciary-duty scrutiny.

4. Complex Concepts Simplified

  • Reformation: a court-ordered fix to a contract’s text so it matches what the parties actually agreed to. It is not “rewriting the deal,” but correcting the document when it misstates the deal due to mistake (or fraud).
  • Mutual mistake vs. scrivener’s error: both sides share (or are equally unaware of) an error in the written expression of their agreement. If everyone agreed to “five years” but the paper accidentally says something else, reformation may correct it.
  • Parol evidence rule (in this setting): normally keeps prior or outside statements from contradicting a final writing. In reformation cases, the point is that the writing is wrong—so outside proof is typically allowed to show the real agreement.
  • Statute of Frauds (in this setting): usually requires certain agreements (like real estate-related agreements) to be in writing. But if the writing exists and the dispute is that it inaccurately reflects the agreed terms, reformation doctrine allows proof to correct the writing.
  • Covenant of good faith and fair dealing: an implied promise that neither party will sabotage the other’s ability to receive the contract’s benefits. It does not create brand-new rights (e.g., an extension of an option deadline) that the contract itself did not provide.
  • Joint venture: a profit-oriented collaboration with shared contributions and shared control, typically including sharing profits and losses. It can be formed orally and inferred from conduct.
  • Terminable at will vs. until a specified result: if no duration is set, the relationship is often terminable at will—but if the venture’s purpose is to achieve a particular project outcome, a court may presume it continues until the goal is achieved. Which applies can be a question for the factfinder.

5. Conclusion

Laun v Stewart is principally a reformation-and-deadline case: where strong, consistent proof shows the parties agreed to a five-year lease term, the court will reform the writing even if the text suggests a longer duration, and that reformation can extinguish an option-based litigation strategy premised on the longer term. The decision also delineates limits on good-faith claims against an optionor who sells only after expiration and does not pre-expiration bind itself to undercut the option. At the same time, it keeps fiduciary-duty exposure alive among former co-operators by treating termination and the scope of continuing duties as fact questions—particularly where the venture’s objective may not have been completed when one side acquired the central asset.