This paper focuses on the use of the providers' web and phone tools, and the data sharing arrangements they built through ad networks and tracking services like Data Dog. It doesn't talk about how they handle data from API calls. For one thing that can be pretty opaque.

I have a friend/client who understandably doesn't trust the existing privacy policies of the major providers. They have the same problem many of us do: We want the most powerful models, we're willing to pay for them, but we see over and over how much of a frontier the frontier actually is. Frontiers are ugly if you don't have guns.

So for now maybe platform tools like Open WebUI and TypingMind are a good workaround since the big boys don't (apparently) train on API data (for now) or (probably) send that data to advertisers. It would be interesting to confirm that.