California Code, Civil Code - CIV § 884.010

(a) If the expiration date of the option is ascertainable from the recorded instrument, six months after that expiration date.

(b) If the expiration date of the option is not ascertainable from the recorded instrument or the recorded instrument indicates that the option provides no expiration date, six months after the date the instrument that creates or gives constructive notice of the option is recorded.

(c) This section shall become operative on January 1, 2013.