Which hedge funds?
There are many companies that offer the data for sale. The example I link seems to require HIPAA authorization from the individual, but the authorization is not actually required by law. It also raises the question how the vendor is able to acquire the data without HIPAA authorization.
The data is advertised as "real time".
For what it's worth, my money is on "deanonymizing" guids. Hedge funds want to track sales in real time to have an edge in earnings forecasts.
(Or whether what they’re doing is borderline legal to begin with)
Yes it will! Because then other people can confirm your claims.