Irrational Games, the studio behind BioShock Infinite, has lost two more developers, LinkedIn profiles have revealed (via Kotaku).

Earlier this month Artificial Intelligence lead Don Norbury and combat design director Clint Bundrick packed their desks at the Boston-based studio to begin new careers at Microsoft. The pair aren't the first to leave Irrational for Microsoft, following producer Joe Faulstick who made the same move back in May.

Irrational and 2K declined to comment on the departures.

Earlier this year Irrational made the high profile signing of Rod Fergusson, a fan favourite over at Epic Games and instrumental in the success of the Gears of War franchise.

A new trailer for BioShock Infinite is expected on Sunday, whilst the game's release remains set for February 2013.