Cal. Rules of Court, rule 8.889

(a) Power to order rehearing

(1) On petition of a party or on its own motion, the appellate division may order rehearing of any decision that is not final in that court on filing.

(2) An order for rehearing must be filed before the decision is final. If the clerk's office is closed on the date of finality, the court may file the order on the next day the clerk's office is open.

(b) Petition and answer

(1) A party may serve and file a petition for rehearing within 15 days after the following, whichever is later:

(A) The decision is sent by the court clerk to the parties;

(B) A publication order restarting the finality period under rule 8.888(a)(2), if the party has not already filed a petition for rehearing, is sent by the court clerk to the parties;

(C) A modification order changing the appellate judgment under rule 8.888(b) is sent by the court clerk to the parties; or

(D) A consent is filed under rule 8.888(c).

(2) A party must not file an answer to a petition for rehearing unless the court requests an answer. The clerk must promptly send to the parties copies of any order requesting an answer and immediately notify the parties by telephone or another expeditious method. Any answer must be served and filed within 8 days after the order is filed unless the court orders otherwise. A petition for rehearing normally will not be granted unless the court has requested an answer.

(3) The petition and answer must comply with the relevant provisions of rule 8.883.

(4) Before the decision is final and for good cause, the presiding judge may relieve a party from a failure to file a timely petition or answer.

(c) No extensions of time

The time for granting or denying a petition for rehearing in the appellate division may not be extended. If the court does not rule on the petition before the decision is final, the petition is deemed denied.

(d) Effect of granting rehearing

An order granting a rehearing vacates the decision and any opinion filed in the case. If the appellate division orders rehearing, it may place the case on calendar for further argument or submit it for decision.