Definitions for "Proof of Service"
A form that lists which interested persons have been served with appropriate notice of a document, particular action, and/or court hearing. A court file generally cannot be heard by the judge until the responsible party has indicated to the court, through this form, that all interested persons have been served with a copy of the relevant petition or motion, and the notice of hearing.  For "court call" (aka "motion call"), only files in which a proper proof of service has been filed will be highlighted on the court docket sheet in yellow as "ready for court."  Those parties may proceed directly to the courtroom.  If the file is not highlighted, it generally means that the responsible party needs to file a proof of service with the court. See court call.  PC 564
A form filed with the court that proves that court papers were properly served on (delivered to) someone.
The form filed with the court that proves the date on which the documents were formally served on a party in a court action.