A copy of birth certificate, obtained, revealed the sex of the child and mentioned he was born on March 17, reported TMZ.
The 39-year-old actress was reported late last week to have given birth to their third child, but details of the newborn were not available.
No other details are disclosed
Fisher and Cohen, 43, have been married since 2010. They already have two daughters together, Olive, 7, and 4-year-old Elula, before reports of the movie beauty's third pregnancy surfaced in October last year.