During the probate process in California, the DE-135 Proof of Holographic Instrument form is necessary when you are trying to validate a holographic will, which is a will written entirely in the decedent's handwriting. This form is typically needed when you are involved in proving that the handwritten document is indeed the valid last will and testament of the deceased person, without it being formally witnessed. - Submission of a petition for probate is usually done before this step, which initiates the entire probate process. - You may need to demonstrate that other forms like the DE-111 (Petition for Probate) have been appropriately filed to begin the process. - The need for this form is triggered when the estate contains a will not meeting formal legal requirements, such as lacking witnesses, but is intended to be treated as a valid holographic will. - It is often required when there is a need to provide evidence of the decedent’s handwriting to the court. After gathering this evidence and submitting the DE-135, the court will assess whether the submitted document can be accepted as the decedent’s enforceable will. The form acts as a crucial evidentiary component to establish the validity of the will during probate proceedings.