I mean, if you want to get into it, you're both right and wrong.
The second largest cases are typically against hospital chains that encourage (read: basically force) their coding teams to use particular billing codes. It's easy enough to model this from claims data (and we did). When a chain buys a new hospital, suddenly patients that present with the same diagnosis codes are all getting extensive exams that ostensibly require 45+ minutes of a physician's time and cost 4-10x more.
Again - the large operators (hospital chains) absolutely dwarf individuals (doctors). DOJ barely has the resources to prosecute the largest offenders, and have faced repeated budget cuts. Wasting time on individual doctors or private practices (beyond maybe making examples of a few egregious actors) would be an inefficient allocation of their resources.
Do you know the details of Palantir's investigation? How do you know they're not doing exactly what you just described? Palantir is just a data analysis company, they're not the NSA.
That's a huge part of the multi billion dollar fraud that Medicare has.
I assume being able to identify physicians will outlier billing patterns would be helpful in figuring out where to look closer.