From Wikipedia: ““Embrace, extend, and extinguish” (EEE), also known as “embrace, extend, and exterminate”, is a phrase that the U.S. Department of Justice found that was used internally by Microsoft to describe its strategy for entering product categories involving widely used standards, extending those standards with proprietary capabilities, and then using those differences in order to strongly disadvantage its competitors.”

It’s relevant today because Meta is trying to join the fediverse, and has reportedly invited Mastodon admins to meetings under NDA. There has been discussion on Lemmy as to weather Meta instances should be allowed to participate or not. Search " anti-meta fedi pact" for more info.