Zipper Interactive was developing two unannounced titles before it was closed by Sony - including a first-person shooter for PlayStation 4.
According to former designers at the studio, the SOCOM: US Navy Seals developer was building the unannounced FPS around a new IP, with the two projects being "halted upon the dissolution of the studio".
There aren't any clues as to what type of game the second title could have been.
Zipper Interactive's final title was PlayStation Vita shooter Unit 13, which released three weeks prior to the studio's closure in March 2012.
The studio was most famous for its work on tactical third-person series SOCOM and online FPS MAG.