Cal. COM § 2201

(1) Except as otherwise provided in this section, a contract for the sale of goods for the price of five hundred dollars ($500) or more is not enforceable by way of action or defense unless there is a record sufficient to indicate that a contract for sale has been made between the parties and signed by the party against whom enforcement is sought or by the party’s authorized agent or broker. A record is not insufficient because it omits or incorrectly states a term agreed upon but the contract is not enforceable under this subdivision beyond the quantity of goods shown in the record.

(2) Between merchants if within a reasonable time a record in confirmation of the contract and sufficient against the sender is received and the party receiving it has reason to know its contents, it satisfies the requirements of subdivision (1) against the party unless notice in a record of objection to its contents is given within 10 days after it is received.

(3) A contract which does not satisfy the requirements of subdivision (1) but which is valid in other respects is enforceable:

(a) If the goods are to be specially manufactured for the buyer and are not suitable for sale to others in the ordinary course of the seller’s business and the seller, before notice of repudiation is received and under circumstances which reasonably indicate that the goods are for the buyer, has made either a substantial beginning of their manufacture or commitments for their procurement;

(b) If the party against whom enforcement is sought admits in its pleading, testimony, or otherwise in court that a contract for sale was made, but the contract is not enforceable under this provision beyond the quantity of goods admitted; or

(c) With respect to goods for which payment has been made and accepted or which have been received and accepted (Section 2606).

(4) Subdivision (1) of this section does not apply to a qualified financial contract as that term is defined in paragraph (2) of subdivision (b) of Section 1624 of the Civil Code if either (a) there is, as provided in paragraph (3) of subdivision (b) of Section 1624 of the Civil Code, sufficient evidence to indicate that a contract has been made or (b) the parties thereto, by means of a prior or subsequent written contract, have agreed to be bound by the terms of the qualified financial contract from the time they reach agreement (by telephone, by exchange of electronic messages, or otherwise) on those terms.