Tom Gruber, an artificial intelligence expert who cofounded Siri, Inc., prior to its purchase by Apple, has announced his retirement from the company, becoming the last of Siri's three cofounders to leave Apple.

According to a report Wednesday night by The Information that was confirmed by Apple, Gruber has announced his retirement, and will now devote his energies to pursuing "personal interests in photography and ocean conservation."

The site reported that Vipul Ved Prakash, Apple's head of search, is also out.

Gruber most recently had been working as head of Siri's Advanced Development group; new hire John Giannandrea recently assumed leadership of the overall Siri team.

A computer scientist who spent the early part of his career in academia, Gruber did a stint at Stanford in the 80s and 90s, before entering the private sector as Chief Technology Officer of enterprise software firm Intraspect Software.

In 2007, Gruber became the cofounder of Siri, Inc., which was acquired by Apple three years later, with the Siri feature soon incorporated into the iPhone and later other Apple products.

In a TED conference talk in 2017 called "Our Robotic Overloads," Gruber predicted that while some fear artificial intelligence replacing humanity, it's better for the technology to augment humanity.

"What if you could have a memory that was as good as computer memory and is about your life? What if you could remember every person you ever met," Gruber said. "How to pronounce their name?" Their family details? Their favorite sports? The last conversation you had with them?"

The same website, The Information, published an overview in March of the Siri team's long history of acrimony and infighting, which has been linked to Siri falling behind Apple and Google's counterparts.