The 27-year old Germen was designated for assignment on Jan. 13 by the Yankees after he was acquired in a trade with the New York Mets the previous month.
In 25 relief appearances for the Mets, Germen pitched in 30 1/3 innings and compiled a 4.75 ERA. He missed a little over a month of the 2014 season because of a virus and abscess.
Over the last two seasons, Germen made 54 relief appearances for the Mets.
The Rangers have bolstered their bullpen this offseason to create depth with a mixture of veterans and young players.