There's also *fourth-party* collection, when the NSA hacks into another security agency that, in turn, has hacked into *another* security agency, and the NSA steals *all* the secrets of *both* agencies:
www.techdirt.com/2015/01/21/s...
techdirt.com
Snowden Documents Show NSA Can't Keep Its Eyes On Its Own Papers; Harvests Data From Other Surveillance Agencies
NSA Milkshake (PDF) NSA Milkshake (Text) Fifth Party Rabbit Hole (PDF) Fifth Party Rabbit Hole (Text) Destroy (PDF) Destroy (Text)