CA Civ Code Section 8508

A stop payment notice is not valid unless both of the following conditions are satisfied:

(a)

The claimant gave preliminary notice to the extent required by Chapter 2 (commencing with Section 8200).

(b)

The claimant gave the stop payment notice before expiration of the time within which a claim of lien must be recorded under Chapter 4 (commencing with Section 8400).