Contract Modification

MBEMax wiki article — paired with the Contracts question set on mbemax.com.

One-line summary

Modifying a contract at common law requires new consideration (preexisting-duty rule); under UCC Article 2, no new consideration is required if the modification is made in good faith.

Mnemonic

CL-UCC-SOF — Common-Law (new consideration); UCC (good faith, no consideration); Statute Of Frauds trigger.

Common-law modification

• Preexisting-duty rule. A promise to do what one is already contractually bound to do is not consideration. Modifications without new consideration are unenforceable.
• Exceptions:
  • Unforeseen difficulties — fairly modest modification to reflect unanticipated burden is enforceable (Angel v. Murray; Restatement § 89).
  • Mutual rescission followed by new contract — parties mutually discharge and form fresh contract with new consideration.
  • Material modification for both sides — each party giving up something new.
  • Promissory estoppel — modification enforceable to the extent reliance requires.
  • Recission + novation — new contract with substituted party.

UCC § 2-209 — goods modifications

• § 2-209(1) — agreement modifying contract within Article 2 needs no new consideration to be binding.
• Good faith required (comment 2) — objective bad faith (using modification to extort new terms without legitimate reason) makes modification unenforceable.
• § 2-209(2) — no-oral-modification (NOM) clauses enforceable; but modification between non-merchant and merchant requires separate signature of non-merchant.
• § 2-209(3) — modification must satisfy Statute of Frauds if the modified contract falls within § 2-201 (e.g., raising price above $500 threshold).
• § 2-209(4)-(5) — attempted modification failing SOF may still be a waiver; waivers may be retracted if reasonable notice and other party hasn't materially relied.

Statute of Frauds overlay

• If original contract within SOF: modification altering material term must be written.
• If modification itself causes contract to fall within SOF (e.g., extension of sale to over $500): writing required.
• Oral modification of contract with NOM clause: at common law, often upheld if accepted and acted on; UCC § 2-209(2) enforces NOM clauses with the non-merchant signature exception.

Waiver vs. modification

• Modification = change in contractual terms, requires consideration (common law) or good faith (UCC), may need writing.
• Waiver = intentional relinquishment of a known right; unilateral, not requiring consideration.
• Retraction of waiver — possible if reasonable notice and no material reliance (UCC § 2-209(5)).

NCBE loves to test

• Preexisting duty. Common-law modification without new concession is unenforceable.
• Unforeseen difficulties exception. Requires unanticipated circumstances AND fairness.
• UCC good faith. Extortion tactics (price hike for no reason) fail the good-faith requirement.
• NOM clauses. UCC enforces except non-merchant signature rule. Common law skeptical but growing acceptance.
• SOF triggers. Modification may pull contract into SOF; writing required.
• Waivers retractable. Clear notice + no reliance = retractable under UCC.
• Estoppel / reliance. Oral modification accepted and relied on may be enforced despite consideration/writing problems.

Fast hypos

Hypo 1. Builder mid-construction demands $5,000 extra "for the trouble." Owner agrees in writing. Common law? Preexisting duty; no new consideration; unenforceable unless unforeseen difficulty or mutual rescission.

Hypo 2. Seller and buyer (both merchants) agree by phone to raise price of lumber from $400 to $550. Original contract had no writing requirement. Under UCC, modification pulls total over $500 → SOF requires writing. Oral modification may be waiver until retracted.

Hypo 3. Contract has NOM clause. Parties later orally agree to extend delivery date. Seller delivers late; buyer sues. UCC — NOM enforceable generally; oral modification may still function as waiver; buyer may be estopped if seller relied.

Hypo 4. Subcontractor agrees to extra work for no new pay because of weather delays caused by owner's prior work. Unforeseen difficulty OR mutual rescission argument; modification may be enforceable even at common law.

Hypo 5. Installment contract. Buyer initially refuses to accept defective installment; seller says she'll accept, no refund. Buyer relies. Seller later retracts. Waiver by buyer; retractable if reasonable notice + no material reliance.

Case anchors

• Alaska Packers' Ass'n v. Domenico, 117 F. 99 (9th Cir. 1902) — preexisting-duty rule applied against fishermen.
• Angel v. Murray, 322 A.2d 630 (R.I. 1974) — modification without consideration upheld due to unforeseen difficulties.
• Roth Steel Products v. Sharon Steel, 705 F.2d 134 (6th Cir. 1983) — UCC good faith applied to price modification.
• Wisconsin Knife Works v. National Metal Crafters, 781 F.2d 1280 (7th Cir. 1986) — § 2-209(2) NOM analysis.

See also

• Offer and Acceptance
• Consideration
• Statute of Frauds
• Parol Evidence
• UCC — Sales

Sources

Restatement (Second) of Contracts §§ 73, 89; UCC § 2-209; Alaska Packers' Ass'n v. Domenico, 117 F. 99 (9th Cir. 1902); Angel v. Murray, 322 A.2d 630 (R.I. 1974); Roth Steel Products v. Sharon Steel, 705 F.2d 134 (6th Cir. 1983); Wisconsin Knife Works v. National Metal Crafters, 781 F.2d 1280 (7th Cir. 1986).