Update 2: VentureBeat reports that the paralegal responsible for The Last Guardian trademark at Sony left the company in January. The site comments:
"Interestingly, Kiphanie Radford, the member of Sony Computer Entertainment America’s legal team that was in charge of filing the trademark information for The Last Guardian is no longer with the company, according to her LinkedIn profile. Radford joined the legal firm Cobalt earlier this year."
Update 1: Sony France has told gameblog.fr that The Last Guardian is still in development.
Original Story: Sony has abandoned its trademark for The Last Guardian with the United States Patent and Trademark Office (USPTO).
The USPTO comments that the trademark was "Abandoned because no Statement of Use or Extension Request timely filed after Notice of Allowance was issued."
This isn't the first time Sony has abandoned the trademark, having previously done so in 2012. It's unknown at this time if Sony intends to submit a new trademark application.
The Last Guardian was first announced in 2009 as a PlayStation 3 game from the team behind Ico and Shadow of the Colossus. Players would take on the role of a young boy and a giant hybrid creature to solve puzzles and progress through the story.
Sony has consistently denied that the game has been cancelled, saying they "laughed" at rumours last summer. It's possible that Sony intends to re-reveal the game under a different title.
As recently as December, game director Fumito Ueda – who began the project at Sony but now works as an outside consultant on the game – said progress was being made "under completely new conditions."
