Rise of the Tomb Raider recently released on the PS4 to strong reception and work on the third game is likely in production…..but now we might know the games official name. Spotted on Imgur from a user, someone from Crystal Dynamics/Square Enix USA was working on a presentation for the game. 
This is a RUMOR, so this could easily be false. But this is great news for those who are enjoying the reboot series of Tomb Raider.
Source: NeoGaf