California Code, Code of Civil Procedure - CCP § 488.450

To attach a security, the levying officer shall comply with Section 8112 of the Commercial Code. The legal process referred to in Section 8112 of the Commercial Code means the legal process required by the state in which the chief executive office of the issuer of the security is located and, where that state is California, means personal service by the levying officer of a copy of the writ of attachment and notice of attachment on the person who is to be served.