Cal. Probate Code - PROB § 19150. Section 19150.
(a)
A claim may be filed by the creditor or a person acting on behalf of the claimant.
(b)
A claim shall be filed with the court and a copy shall be delivered to the trustee pursuant to Section 1215. Failure to deliver a copy to the trustee does not invalidate a properly filed claim, but any loss that results from the failure shall be borne by the creditor.
