The 83-year-old cult leader was serving a life sentence for murdering pregnant actress Sharon Tate, along with six others.
Although Manson was not the one who murdered, it was he who instructed his cult members to do so.
It was TMZ who first obtained the cult leader's death certificate, which lists cardiac arrest as the immediate cause of his death.
TMZ also reports that the death certificate did not list a mother or father.
This article originally appeared on New Idea.