Historically, it always seemed like it was one company though as Adblock codebase has been based on Adblock plus codebase for years, and they both use Acceptable ads.
Edit to avoid confusion: Fake "uBlock" (not to be confused with uBlock Origin) is owned by AdBlock https://www.ublock.org/blog/an-update-on-ublock/
uBlock is a scam
https://en.wikipedia.org/wiki/UBlock_Origin#uBlock https://ublock.org
µBlock/uBlock was the original, released in 2014 by Gorhill. In 2015, fed up with support request, he transferred the project to Chris Aljoudi. He then forked his own project, most likely due to a disagreement over donations, it became uBlock Origin. Eventually most people moved from uBlock to the better maintained uBlock Origin. Eyeo eventually bought uBlock and added their "acceptable ads" option.
So you can't say that uBlock is a fake, it is actually the original project. But the one made by the original author is uBlock Origin.
Yes it is confusing, but whatever, get uBlock Origin.
The essence of a project is not the location of its repo on GitHub, it's who worked on it since it was first created, i.e. the commit history. If you look at the commit history of "uBlock Origin", it goes back without interruption to June 23rd, 2014, back to when I created the repo.[1]
The claim that the current "uBlock" is the "official", "original" project is a marketing pitch by the people behind it, who I call out as purposefully deceitful.[2]
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