California Code
CHAPTER 1 - General Provisions
Section 368.

368. In the case of an assignment of a thing in action, the action by the assignee is without prejudice to any set-off, or other defense existing at the time of, or before, notice of the assignment; but this section does not apply to a negotiable promissory note or bill of exchange, transferred in good faith, and upon good consideration, before maturity.

(Enacted 1872.)