California Code, Unemployment Insurance Code - UIC § 607

If the services performed during one-half or more of any pay period by an employee for the person employing him constitute employment, all the services of the employee for that period shall be deemed to be employment; but if the services performed during more than one-half of any pay period by an employee for the person employing him do not constitute employment, then none of the services of the employee for that period shall be deemed to be employment.

As used in this section “pay period” means a period of not more than 31 consecutive days for which a payment of remuneration is ordinarily made to the employee by the person employing him.