Eidos Montreal is a Canadian video game development studio owned by Eidos Interactive, a subsidiary of Square Enix. The studio was founded by Eidos in 2007 with Stéphane D'Astous appointed studio manager. According to D'Astous, unlike other video game development studios Eidos Montreal's development cycle is characterized by smaller teams (totaling 350 people) working over a longer period. The same year as its founding, the studio announced its first project: the third installment of the Deus Ex series, Deus Ex: Human Revolution, which was released in 2011. In 2009 the studio announced its second project, the fourth installment of the Thief series.
Source: Wikipedia, "Eidos Montreal", available under the CC-BY-SA License.