It was reported last month that Allen had been suspended from the post he had held since January 2015 because he was "too close" to Lawrence Tomlinson, who is looking to take over the track.
Allen said: "Some of you may have heard, or seen in the press, some rumours about my departure.
"It is true some allegations were made against me but, for the avoidance of doubt, these have all been withdrawn."
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Patrick Allen has quit as the managing director of Silverstone