FWIW, from my last reading of their privacy policy, they openly stated that they do share PII with other companies who they consider to be their partners.

They claim that they don’t share PII with third parties “for their marketing purposes”.

That being said, you’re at the mercy of their definition of “partner” and interpretation of “for [the third party’s] marketing purposes”.

I should honestly just re-read their privacy policy (and the same for Google and Meta).