[crazygringo]

As other commenters here have noted, a company can't just do this accidentally. If they add an external group, there's a warning message. Because many times it may be a mistake, but there are also many times a company will have a legitimate reason to do so.

This isn't a bug, it's a feature. If you want to do the right thing, the correct course of action isn't to notify Google, it's to send an e-mail to the companies so they can revoke access to the group. It's not Google's problem.

Or if you don't want to deal with that and the group isn't used for anything anymore and you still want to be a good citizen, just delete everybody else from the group.

[anon223345]

I’m just going to delete the group

[anonymouskimmer]

Bad idea. You're a good person, the next person to create the group name (which you've helpfully published here) may not be.