14 CFR § 145.213

A certificated repair station must inspect each article upon which it has performed maintenance, preventive maintenance, or alterations as described in paragraphs (b) and (c) of this section before approving that article for return to service.

A certificated repair station must certify on an article's maintenance release that the article is airworthy with respect to the maintenance, preventive maintenance, or alterations performed after—

The repair station performs work on the article; and

An inspector inspects the article on which the repair station has performed work and determines it to be airworthy with respect to the work performed.

For the purposes of paragraphs (a) and (b) of this section, an inspector must meet the requirements of § 145.155.

Except for individuals employed by a repair station located outside the United States, only an employee appropriately certificated as a mechanic or repairman under part 65 is authorized to sign off on final inspections and maintenance releases for the repair station.