There was not enough detail about the threat to launch a criminal proceeding, spokeswoman Judith Henkel told the Funke newspaper group.
"There was no match among the names we received... to people living or registered in Germany," she said.
Authorities in Munich locked down two stations, including the main station, with teams of heavily-armed police on New Year's Eve after they received a bomb threat.
The precautionary move was based on a warning naming seven individuals behind the supposed attack.
But neither police nor prosecutors have oncovered any leads on the names given in the message.