LONDON, Sept 12 (Reuters) - British housebuilding stocks tumbled on Tuesday as big share sales by company founders and growing pessimism among analysts reignited concerns over the resilience of a sector which had enjoyed a strong rally since the Brexit vote.
The founder and chairman of property developer Redrow , Steve Morgan, sold 25.9 million shares in the company through his charity foundation on Monday evening, sinking the shares 7 percent on Tuesday.
Tony Pidgley, founder and chairman of Berkeley Group , sold 750,000 shares in the housebuilder last week, sending stocks across the sector lower.
"When Tony Pidgley and Steve Morgan sell shares in the companies they founded, investors take notice and ask if the silverback alpha males in the sector are calling the top of the market," said Jefferies analysts.
Their note, titled "Gurus calling the top?", said the sales were particularly striking as they took place in the face of supportive factors including Britain's housing shortage and the stimulus of the government's Help to Buy policy.
The FTSE index of housebuilders and property developers has rallied around 25 percent since the Brexit vote.
The vote to leave the EU initially hit sectors exposed to the domestic economy, chief of all housebuilders. But as the worst fears over the immediate economic impact of the vote failed to emerge, builders more than bounced back, cemented by investors' confidence demand for housing would be resilient.
High dividend payouts also kept investors in the shares of the likes of Barratt Development and Persimmon, which have surged between 30 and 43 percent. Redrow had notched up 50-percent gains before Tuesday's fall.
But the sector suffered another sell-off in early August after a report cast doubt over the Help to Buy scheme, indicating how much the earlier rally had depended on that stimulus.
Investors have also started to worry the rally may have gone too far and increasingly scrutinised forward-looking guidance more than results.
Shares in Berkeley Group and Barratt Developments fell last week after striking a cautious tone in their outlook, even though first-half results were in line with expectations.
"In the short term I think are too high," said one trader, who asked not to be named.
Analysts at Bank of America Merrill Lynch said the sector was highly priced and risks lurked ahead including the future of Help to Buy, the uncertain direction of interest rates and falling consumer confidence.
(Reporting by Helen Reid; Editing by Andrew Heavens)