Andrew Vaughan, the managing director, Steven Kent, finance director, and Andrew Bridson, business development director, will each pocket nearly pounds 3.1m for their respective 3.8 per cent stakes. They are to remain with the company.
Workers at the Stevenage-based firm will also share in the spoils through an employee trust fund that owns a 3.9 per cent interest.
Workplace was originally spun out of ICL through a management buyout in 1995. The company floated on the stock market in late 1997 at 175p.
Venture capital giant 3i is the biggest shareholder with a 22.5 per cent interest, followed by Barclays with 6.2 per cent, Norwich Union with 4.8 per cent and Equitable Life, 4.8 per cent.
"The acquisition will significantly strengthen our ability to be the total communications service provider for our business customers," said NTL.
Workplace stock had lagged in recent months and traded at 145p on Tuesday before rumours of the 228p per share bid began circulating.