Ask HN: What does "Used by engineers at [Company]" for OSS mean? Stars/emails?

I've got a popular Github project, and want to start putting some "social proof" on the README. But since it's open source and we don't have a login, I don't know definitely who is using it for what (by design, and I'd like to keep it that way).

What I do have:

- Lots of Github stars from engineers at top companies (Apple, Disney, etc). - People who subscribed to our mailing list with corporate emails

Is this the type of content people use to build out those lists? Is there a better phrasing of the title that implies it comes from sources like this (vs contracts which is what I expect for a SaaS company)? Any other gotchas I should be aware of?