Comment by Clamchop

I've looked into it before and I didn't find anything suggesting that it's a law. It appears to be willful collaboration with the feds and other nation states, possibly to avoid the attention of regulators, but it's all done in secret so there's not a ton of info.

Along similar lines, scanners and commercial software packages like Photoshop attempt to detect EURion dots and the digital watermarking that replaced it in currency. Obviously open source software has no such thing because it would be pointless, and it's not illegal that it doesn't.

For whatever reason, these antifeatures seem to also be missing from commercial digital cameras.