Tusla has handed over files on fake birth certs to the gardaí.
Child protection experts are investigating after allegations that adopted parents were illegally listed as birth parents for years.
At least 126 cases have been found at the St Patrick's Guild adoption agency between the 1940s and 1960s.
But it's feared there may be many more.
The Times says the gardaí are now preparing a file for the DPP.