User blog comment:Deathmanstratos/Call of Duty: Advanced Warfare "Induction" Singleplayer mission shown/@comment-3964768-20140610223135/@comment-3171236-20140611011023

Tiatnfall has been in development since 2011. Call of Duty: Advanced Warfare has been in development since 2012 (3 years of production: 2012, 2013 and most of 2014).

I highly doubt they would copy one another, since Respawn Entertainment does not seem interested in using Call of Duty's ideas, and Sledgehammer Games has not used big mechs or any of Titanfall's style in the game.