Exactly. Thank you.

The slippy slope here is already in operation. It's the entire rationale behind prohibiting targeting based on zip code: demographics change from zip code to zip code, so the HUD concludes that targeting by zip code is de facto targeting by demographic.

What logical basis is there for stopping at zip code targeting and not applying the same logic to other demographic correlates?

> The slippy slope here is already in operation.

Except there are 40 years of court decisions clarifying how the law should be interpreted.

Most of the case law dates from before internet advertising microtargeting. We're in novel legal territory here.

That said, it's possible that a forward-thinking court has already resolved the question under discussion. Can you point me to case law that discusses the boundary between discriminatory and non-discriminatory ad targeting based on demographic correlates?

The fact it’s an online entity may or may not be novel (I imagine Craig’s List has been sued over this).

I meant my comment to refer to the idea of a slippery slope on what does/does not count as a discriminatory. There is lots of case law on that.

I think it’s safe to say if a court has previous rules you can’t put ‘No X’ or ‘Y only’ in a newspaper ads you can use t as a filter for ad targeting.