Cal. Commercial Code § 9403

(a) In this section, “value” has the meaning provided in subdivision (a) of Section 3303. (b) Except as otherwise provided in this section, an agreement between an account debtor and an assignor not to assert against an assignee any claim or defense that the account debtor may have against the assignor is enforceable by an assignee that takes an assignment that satisfies all of the following conditions: (1) It is taken for value. (2) It is taken in good faith. (3) It is taken without notice of a claim of a property or possessory right to the property assigned. (4) It is taken without notice of a defense or claim in recoupment of the type that may be asserted against a person entitled to enforce a negotiable instrument under subdivision (a) of Section 3305. (c) Subdivision (b) does not apply to defenses of a type that may be asserted against a holder in due course of a negotiable instrument under subdivision (b) of Section 3305. (d) In a consumer transaction, if a record evidences the account debtor’s obligation, law other than this division requires that the record include a statement to the effect that the rights of an assignee are subject to claims or defenses that the account debtor could assert against the original obligee, and the record does not include such a statement, then both of the following apply: (1) The record has the same effect as if the record included such a statement. (2) The account debtor may assert against an assignee those claims and defenses that would have been available if the record included such a statement. (e) This section is subject to law other than this division which establishes a different rule for an account debtor who is an individual and who incurred the obligation primarily for personal, family, or household purposes. (f) Except as otherwise provided in subdivision (d), this section does not displace law other than this division which gives effect to an agreement by an account debtor not to assert a claim or defense against an assignee.