> ThreatExchange (aka TX or TE) is used by multiple companies to share signals on a variety of topics intended to prevent real world harm. Some examples of how TX is currently used include sharing malware, phishing scams, and terrorism signals with the goal of helping all participating organizations tackle these problems based on their terms of service.

https://developers.facebook.com/docs/threat-exchange/getting...

I think it is simply the domain name itself, not anything they did. The domain name he uses (stamhoofd) translates to "head of the tribe/tribal leader". I can imagine that such a word can easily have bad connotations and nobody wants their brand to support any site with a potentially offensive name that can turn into a PR nightmare. Likely it got flagged for this reason.

Good question! I would also like to know the answer. I've scanned through our sites and couldn't find any malicious content... My guess is that the block was automated, and might have been caused by a fake spam report. There can be some competition between non-profits (e.g. two scouting groups in the same local area). Maybe they started to report each other as a joke.