The 364,983 shares were granted in December 2009 instead of a cash bonus and vested at the start of this week.
It was confirmed Sir Brian sold all of his award on Monday at 305.38p per share. He intends to use the proceeds for the Souter Charitable Trust he runs with his wife Betty.
Stagecoach's North American chief executive Dale Moser sold his 89,008 shares, making more than £271,000, while UK bus managing director Les Warneford offloaded his 121,404 award to take in excess of £370,000.
The Perth transport company said each director had settled the payment of tax, duties and social security contributions related to the vesting of the award.
Stagecoach's shares ended last night down 2.9p, or 1%, at 302.4p.