February 2007 - The project was first revealed in a full-page advertisement in Famitsu, the Japanese gaming magazine. The advert featured some concept sketches as well as recruitment advertising for members of the technical and art departments. A teaser image was also released of a chain leading into a hole.
May 2009 - The PlayStation LifeStyle blog leaked the game's first trailer, which showed the boy being chased by Trico, and Trico destroying an Armored Knight with his claw. The boy is chased to the edge of a chasm, where Trico rescues the boy, who then climbs on top of Trico.
June 2009 - An updated version of the trailer that leaked in May was shown at E3 during Sony's keynote press conference.
September 2009 - A second trailer was released at the Tokyo Game Show
September 2010 - The game was again shown at the Tokyo Game Show, and a tentative release date of late 2011 was given. The Team Ico HD Collection was also announced.
January 2011 - A short clip of the game was shown to members of the press, with an embargo date of March 2011.
February 2011 - Ueda stated in interviews that they still aimed to release the game in 2011.
March 2011 - Ueda mentioned the possibility of a demo for The Last Guardian appearing in the Team Ico HD Collection, though this did not ultimately happen.
December 2011 - It was announced that Ueda was leaving Sony, but that he would complete The Last Guardian. The game's executive producer, Yoshifusa Hayama, also announced his departure from Sony at the same time.
February 2012 - Shuhei Yoshida, president of SCE Worldwide Studios, stated that the game was still in development and had not been cancelled.
June 2012 - The Last Guardian did not appear at E3 because of 'technical difficulties'.
August 2012 - Sony affirmed that the game was still in development, that at one point had the game in a playable state, but some technical issues arose and they have had difficulty in resolving them.
