[lern_too_spel]

The documents don't identity them as "participants." They only say when data from those company was ingested into PRISM, which is simply a data integration program between the NSA and the FBI. The FBI's Data Intercept Technology Unit is clearly labeled in the slides.

The government issues a Section 702 order for some account(s) data, the company reviews the request and denies it if the account appears to belong to somebody in the US or an American (both of which cannot have their data requested via a Section 702 order), and then sets up a forward to the FBI. PRISM then geta that data from the FBI and parses it into fields for various NSA databases. Again, this is very clearly drawn out in the system diagram slide that Snowden leaked.