Could This Be The British Ex-MI6 Agent Behind The Trump FBI Memos?
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In 2010, Steele was one of four former British intelligence officers who spoke at a black tie gala dinner in central London (the exact location was kept confidential from the public) that celebrated the 100th anniversary of MI6. There were various sessions held at the event, including ones led by Andrew Rostov, a retired KGB counterintelligence colonel, and Brian Kelley, a retired CIA case officer.
Steele is also a director a UK-based company named Walsingham Training, although his name (nor the names of others) does not appear on its website. The company provides courses to company executives on subjects ranging from Understanding and mitigating the cyber and physical risk posed by hostile states, criminals and companies, to how to gain traction in complex markets like Russia and how to recognize misinformation.
http://www.forbes.com/sites/richardbehar/2017/01/11/could-this-be-the-british-mi6-agent-behind-the-trump-fbi-memos/#3c0d1d2337da
So apparently a fairly senior British spook.