UPDATE 15/9/23: The "credible" death threat that prompted the closure of Unity offices yesterday was made by a Unity employee, police have now revealed.

A statement from San Francisco police, via Polygon, explained that the threat originated from an employee who had "made a threat towards his employer using social media".

The unnamed employee who made the threat did not work in the San Francisco office, and it's unclear what further action is being taken. We'll update if we hear more.

ORIGINAL STORY 14/9/23: In the wake of its hugely controversial engine pricing changes, Unity has closed a number of its offices over what it has called a "potential threat".

News of the temporary closures first began circulating earlier today as Unity employees shared the news on social media. "Hey y'all, just a reminder to think before you target Unity employees," senior XR product designer Javier Busto wrote. "This morning we learned that law enforcement notified several Unity offices of credible threats."

Bloomberg's Jason Schreier later elaborated on those initial reports, writing that a "credible death threat" had resulted in the closer of two Unity offices - in San Francisco and Austin, Texas - as well as the cancellation of a town hall meeting that would have seen Unity CEO John Riccitiello addressing staff following Tuesday's widely lambasted pricing changes.

A Unity spokesperson confirmed the report in a statement provided to Rock Paper Shotgun, writing, "Today, we have been made aware of a potential threat to some of our offices."

"We have taken immediate and proactive measures to ensure the safety of our employees, which is our top priority," the statement continued. "We are closing our offices today and tomorrow that could be potential targets for this threat, and are fully cooperating with law enforcement on the investigation."

Since Unity's announcement on Tuesday that, from 1st January 2024, it would begin charging developers a fee each time a user installed their game on a new device, condemnation has been widespread. Speaking to Eurogamer, The Swindle developer Dan Marshall called the changes an "absolute fucking catastrophe", adding, "I'm legitimately quite angry. I've been using Unity for over 10 years, that's a lot of investment in a system I'm about to drop like a hot rock."

Similar sentiments have been shared by countless other developers; earlier today, Slay the Spire studio Mega Crit wrote, "Despite the immense amount of time and effort our team has already poured into the development on our new title, we will be migrating to a new engine unless the changes are completely reverted and [Terms of Service] protections are put in place."

As the backlash has continued, Unity - which quietly altered its Terms of Service in April to remove a clause that would let developers stick with previous versions of the document if updates adversely impacted their rights - has made minor U-turns on its initial announcement.

Today it was reported Unity is promising a 100% waiver on its new fees to developers if they're willing to switch over to the company's own LevelPlay ad platform.