

Google isn’t the only service checking for csam. Microsoft (and other file hosting services, likely) also have methods to do this. This doesn’t mean they also host csam to detect it. I believe their checks use hash values to determine if a picture is already clocked as being in that category.
This has existed since 2009 and provides good insight on the topic, used for detecting all sorts of bad category images:




I’m being a bit extra but…
Your statement:
The article headline:
The general story in reference to the headline:
The article headline is accurate if you interpret it as
“A Developer Accidentally Found CSAM in AI Data. Google Banned Him For It” (“it” being “csam”).
The article headline is inaccurate if you interpret it as
“A Developer Accidentally Found CSAM in AI Data. Google Banned Him For It” (“it” being “reporting csam”).
I read it as the former, because the action of reporting isn’t listed in the headline at all.
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