[noahkunin]

Gov employee here (18F).

If the operative word is "sent" and "all" the likelihood is zero, as I can assert I've never sent a private key to NSA, and I've made quite a few over the past few years.

That said, carlosdp makes a great point as to how one should behave. Even though not all private keys get shipped to NSA (can't make claims about other teams), the government is very public about other data sharing programs (see https://www.dhs.gov/sites/default/files/publications/privacy... for example).

Even though all government agencies must disclose these types of programs, they are so numerous and often so difficult to decipher, the only rational response is to assume everyone has everything or could have access in the future.

The only way to avoid this is to build zero-knowledge systems on the server side, something I hope you'll see more of in 2017.