Battle of the Forms Under California Commercial Code 2207: Whose Terms Control?
Last updated: November 2026. Reviewed by Pavel Kolmogorov, California business litigation attorney (State Bar No. 321018).
The battle of the forms is the dispute over whose fine print governs when a purchase order and the seller's acknowledgment or invoice conflict. California Commercial Code section 2207 decides it. A contract can form even though the forms disagree, and a term that first appears in the other side's form, such as an arbitration clause, often does not bind a party who never assented to it. (Com. Code, § 2207.) Kolmogorov Law, P.C. litigates these disputes in Orange County, Los Angeles, and across California.
Call (909) 235-6116 or contact us online to discuss which terms govern your purchase orders, invoices, or supply relationship.
What the battle of the forms is
Businesses rarely negotiate the back of a form. The buyer sends a purchase order with its standard terms. The seller answers with an acknowledgment, ships, and sends an invoice, each carrying the seller's standard terms. Nobody reads either set until something goes wrong.
Under general contract law, an acceptance must be absolute and unqualified, and a qualified acceptance is a new proposal. (Civ. Code, § 1585.) The Commercial Code dropped that mirror image rule for goods. A contract for the sale of goods may be made in any manner sufficient to show agreement, including conduct by both parties that recognizes a contract. (Com. Code, § 2204, subd. (1).) Section 2207 asks whether the parties in fact closed a deal, and then sorts out its terms. (Steiner v. Mobil Oil Corp. (1977) 20 Cal.3d 90, 99-100.)
Step one: did the forms create a contract?
A definite and timely acceptance operates as an acceptance even though it states terms additional to or different from the offer. The exception is an acceptance expressly made conditional on assent to those terms. (Com. Code, § 2207, subd. (1).)
The first question is which document was the offer. If the seller's quote was a definite offer and the purchase order accepted it, the seller's terms are the starting point. If the quote was only a price indication, the purchase order is usually the offer. The second question is whether the responding form says, in clear words, that acceptance is conditioned on the other side's agreement to its terms. If it does, it is a counteroffer, and the other side is bound to those terms only by specific and unequivocal assent. Silence and performance are not enough. (Textile Unlimited, Inc. v. A..BMH & Co. (9th Cir. 2001) 240 F.3d 781, 787-788.)
Step two: which added terms become part of the deal
If the forms did create a contract, the extra terms in the acceptance are proposals. Between merchants they become part of the contract unless one of three things is true. (Com. Code, § 2207, subd. (2).)
- The offer expressly limited acceptance to its own terms.
- The new terms materially alter the contract.
- The offeror objected, before or within a reasonable time after receiving them.
A merchant is, in general, a person who deals in goods of the kind or holds itself out as having knowledge of the practices or goods involved, so most business-to-business sales of goods qualify. (Com. Code, § 2104, subd. (1).)
Material alteration is where the fighting happens. The California Supreme Court has described a variation as material if it would result in surprise or hardship if incorporated without the other party's express awareness. (Steiner, supra, 20 Cal.3d at p. 102.) Warranty disclaimers, liability caps, and dispute resolution clauses are the terms most often challenged under that test. Our pages on commercial warranties and limitation of liability clauses cover what those terms do once they are in.
Step three: when the forms never matched but the goods shipped
Sometimes the writings do not make a contract at all, usually because one form was expressly conditional and the other side never agreed. The parties perform anyway. Conduct by both parties that recognizes a contract is then sufficient to establish one. Its terms are those on which the writings agree, together with the supplementary terms the Code supplies. (Com. Code, § 2207, subd. (3).)
The conflicting terms drop out. In Textile Unlimited, the seller's invoices and acknowledgments contained an arbitration clause, the buyer never specifically assented, and the Ninth Circuit held under California law that the clause was not part of the contract formed by conduct. The Code has no gap-filler that supplies arbitration. It does supply implied warranties and remedies, described on our page about sale of goods disputes.
A purchase order naming Orange County courts and an invoice naming Texas arbitration
The buyer's purchase order selects the Orange County Superior Court. The seller ships, and its invoice calls for arbitration in Texas.
If the purchase order was the offer and the seller accepted by acknowledging or shipping, the contract generally formed on the buyer's terms. An arbitration clause arriving later on an invoice is a proposal for an addition to the contract. It stays out if the purchase order limited acceptance to its own terms, if the buyer objects, or if the clause materially alters the deal. A clause that contradicts the forum the order named is hard to call minor. If instead the seller's acknowledgment was expressly conditional on its own terms, there may be no contract on either form, and both dispute clauses fall away. Ordinary jurisdiction and venue rules then decide where the case is heard. Our page on forum selection clauses explains how California courts treat a clause that does survive.
I ask clients to lay every quote, order, acknowledgment, and invoice on one timeline before anyone argues about what was agreed.
If you are the buyer: protecting your purchase order terms
State on the face of the purchase order that acceptance is limited to its terms and that different or additional terms are rejected. Object in writing when a seller's acknowledgment arrives with conflicting terms. Do not let employees sign the seller's credit application or order confirmation without review, because a signature is assent.
If you are the seller: making your terms stick
Make your quote the offer, with your terms attached and a short acceptance period. If the buyer's order arrives first, respond with an acknowledgment that is expressly conditional on your terms, and get a signature or a written confirmation before you ship.
For any relationship that matters, the better answer for both sides is a signed supply agreement with a clause saying it overrides all forms. Later changes then follow the rules on contract modification, an issue that also arises when a supplier tries to add a surcharge mid-contract.
What to bring to the first meeting
- Every quote, purchase order, acknowledgment, packing slip, and invoice, front and back.
- Each side's standard terms and any website terms the forms refer to.
- Emails about the order, especially any objection to the other side's terms.
- Any master agreement, credit application, or signed confirmation.
Frequently asked questions
Our purchase order says disputes go to court in Orange County but the seller's invoice says arbitration in Texas. Which terms control?
It depends on which document was the offer and whether either form made acceptance expressly conditional on its own terms. Under California Commercial Code section 2207, an arbitration clause that first appears in a seller's invoice often does not bind a buyer who never assented to it. If neither form controls, both clauses drop out and ordinary court rules apply.
What is the battle of the forms?
It is the contest between a buyer's and a seller's preprinted terms when each sends its own form for the same sale of goods. California resolves it under Commercial Code section 2207, which allows a contract to form despite the mismatch and then determines which terms from each form, if any, become part of the agreement.
Do purchase order terms or invoice terms control?
Usually the terms of whichever document was the offer. Between merchants, added terms from the other side also become part of the deal unless the offer limited acceptance to its own terms, they materially alter it, or the offeror objects within a reasonable time. In California an invoice sent after the contract was formed generally cannot add terms that materially change the deal unless the buyer agrees. Where both forms conflict and neither was accepted, the conflicting terms cancel and the Commercial Code fills the gaps.
Does section 2207 apply to service contracts?
Not to a contract for services alone. Section 2207 is part of the Commercial Code's division on sales of goods. Under section 2102, a mixed contract in which the goods do not predominate is subject only to that division's provisions that relate primarily to its sale-of-goods aspects. General California contract law otherwise governs, and under it a response that changes the terms of an offer is ordinarily a counteroffer.
We kept paying a supplier's invoices that had terms printed on the back. Did we agree to those terms by paying?
Not automatically. Under California's Commercial Code, payment and performance show that a contract exists, but they do not by themselves establish assent to every term in the other side's form. Terms that materially alter the deal generally require real agreement. Repeated dealings over years can strengthen the supplier's argument, so object in writing once you notice them.
Talk to a California breach of contract attorney
If a dispute turns on whose terms apply, call (909) 235-6116 or contact us online. Kolmogorov Law, P.C. is located at 327 Magnet, Irvine, CA 92618, and represents buyers and sellers of goods in Orange County, Los Angeles, and throughout California. Related reading: our breach of contract practice page and sale of goods disputes.
This page provides general information about California law and is not legal advice. Outcomes depend on the documents exchanged, their order, and the court.