[gonzo]

The OSI emphatically does NOT:

own the trademark of “Open Source”.

They tried, and the USPTO denied their application for same. As such they have any such right to exercise.

They own a trademark for “Open Source Initiative”, and attempt to persuade the public that they alone define the term “Open Source”.

https://opensource.org/trademark-guidelines

[ajb]

Woops, my apologies for spreading misinformation. I genuinely thought they had the trademark, but it's confirmed that they don't: https://opensource.org/pressreleases/certified-open-source.p...

Nevertheless, their Open Source Definition is reasonably respected