FICO stands for fair Isaac corporation, and the 3 reporting agencies are Transunion, Equifax, and Experian. FICO scores come from the information reported to those agencies, which is where the score comes from, but FICO itself isn't a reporting agency. There are several different models of FICO, so it just depends on the agency and if you're applying for something, which model they use.
Then there are "FAKO" scores that aren't official scores, but a ballpark, rather. I looked up which agency capital one uses for their report and I see that's also Transunion.
This is a good read to explain more:
The many flavors of FICO:__Editions, versions, and... - myFICO® Forums