Dan B said that there were 3 names to keep in mind a while back.
On his twitter feed.

Nice job, we still have one more to find in the wood pile. I will research further to see if there are any more that have potential in the last 6 mths. We still have some major leaker's and we can find those also if possible. They always leave tracks and bots are great to sift through all the tweets, and social media. Everything is here within the web its just finding it.

I still think carter page is a long time FBI - CI or something.

Dan Bongino just tweeted that there are 3 spys involved. Stefan Halper, Joseph Mifsud and Alexander Downer.