[linkregister]

This is mostly correct.

The declassified portion of the UK USA agreement [1] doesn't actually mention spying on other members' citizens, as the purpose of the agreement was to establish the scope of shared information during the Cold War.

The prohibitions on collection were made during subsequent agreements and aren't declassified. Some countries have additional restrictions, such as prohibiting other members from collecting metadata; all prohibit collection of actual message content.

Of course, a country could defy the agreement and existing treaties, and collect. I haven't seen any evidence of this in the Snowden leaks though.

1. https://www.nsa.gov/news-features/declassified-documents/uku...