Persimmon's shares fell 4% to 442p on Monday as the City reacted to the rumours. Other casualties were Wimpey (down 3% to 275p), Redrow (down 3% to 285.5p), and Bovis HOmes (down 2% to 411p).
Brown has raised the tax on house purchases four times since he became chancellor in 1997, but has left the rate unchanged since March 2000. Now the election is out of the way, many fear he is casting a rapacious eye at the thriving housing market as he looks for ways to finance the government's highly ambitious capital investment plans.
The basic rate of stamp duty now stands at 1%, rising to 3% for properties worth £250,000 to £500,000 and 4% for those worth £500,000-plus. On the other hand, if the chancellor calculates that any further increases will cross the taxpayers' pain threshold, he will probably leave rates unchanged.