California Code, Education Code - EDC § 44929.27

No employee of a school district or districts, in which the average daily attendance of all the districts combined is in excess of 200,000, governed by the same governing board shall hereafter acquire permanent certificated tenure or permanent noncertificated status, or a combination of tenure and status, for more than one full-time position.  Any employee who hereafter acquires any combination of permanent certificated tenure or permanent noncertificated status or both which exceeds that for one full-time position shall have a choice which tenure or status to retain so long as that retained does not exceed one full-time position.

It is the intent of this section that an employee holding permanent certificated tenure or permanent noncertificated status for a full-time position may not have permanent tenure or status protection for any additional time in either a certificated or a noncertificated position under any such school district governed by the same governing board.