The document, filed with L.A. County, says Petty passed away at 8:43 PM on Oct. 2 at UCLA Santa Monica.

The certificate lists the immediate cause of death as "deferred" -- which could mean officials are still waiting for autopsy results.

Here's what else is listed on the certificate:

-- Marital status: Married to Dana Marie York

-- Full Name: Thomas Earl Petty

-- Education: High school graduate

-- He lived in Malibu for 43 years

-- Race: Caucasian

-- Career: Songwriter & musician who worked in the field for 40 years

As we first reported ... Tom was rushed to the hospital after he'd gone into full cardiac arrest and was found unconscious and not breathing. He was eventually taken off life support, and died last Monday.

He was 66.