California Code, Probate Code - PROB § 9732

(a) The court may order that money of the estate in possession of the personal representative be invested in any manner provided by the will if all of the following conditions are satisfied:

(b) To obtain an order under this section, the personal representative or any interested person shall file a petition showing the general condition of the estate and the types of investments that are proposed to be made.

(c) Notice of the hearing on the petition shall be delivered as provided in Section 1220. In addition, the petitioner shall cause notice of the hearing and a copy of the petition to be delivered pursuant to Section 1215 to all known devisees of property which is proposed to be invested. Where the property proposed to be invested is devised to a trust or trustee, notice of the hearing and a copy of the petition shall be delivered pursuant to Section 1215 to the trustee or, if the trustee has not yet accepted the trust, to the person named in the will as trustee.Delivery pursuant to this subdivision shall be to the person's last known address as provided in Section 1220.

(d) If no objection has been filed by an interested person, the court may make an order authorizing or directing the personal representative to invest such portion of the money of the estate as the court deems advisable in the types of investments proposed in the petition and authorized by the will. If there is no objection by an interested person and no substantial reason why some or all of the investment powers given by the will should not be exercised, the court shall make the order. The order may be for a limited period or until the administration of the estate is completed. Upon petition of the personal representative or any interested person, the order may be renewed, modified, or terminated at any time.