[talldayo]

In the United States, any ageism will usually exist at an administrative/personal level. Age is an equal-opportunity attribute that cannot be legally discriminated against, so on paper all of them will technically claim to be "friendly". I don't know how you'd really compile a list like that any more than you'd make a "junior friendly" hiring list.

[rndaom]

Anecdotal evidence from people already working there. It's not a list of companies breaking the law but the inverse. A list of companies that we know from inside that they are fully OK with older age. This is to save aged job seekers time dealing with the rest that will fail them deeper in the interview process once they figure out they are older.

[tracker1]

Same as any other $IMMUTABLE_CHARACTERISTIC-friendly company. I would think that any such statements might be mostly meaningless. It's really hard to say.

You can't even rely on the apparent age of senior management as a rough guide.

[Lutger]

I don't think meaningless is the right word. It would be deeply meaningful for a woman to know if a company is inclusive to her needs, for someone of color to know if a company isn't racist, etc.

The information is sensitive and damages companies reputation who are explicitly not on the list. Except maybe, these days, if a company wants to be known for its non-wokeness or such nonsense. Maybe one of Musk companies?

However, I do think this is an opportunity for sites like glassdoor.

[tracker1]

If everyone is $foo-friendly, it becomes meaningless... it's mostly marketing at that point. It's the HR side of hot-new-shiny, where consulting companies have a product to sell even if it makes no sense in practical terms.