Rightmove chairman sells almost half his shares for £7m

The chairman of Rightmove has sold almost half of his shares in the UK's biggest property website for £7m.

Scott Forbes, who has been Rightmove's chairman since 2005, sold 300,000 shares at an average price of £23.50. He retained 319,300 shares in the 14-year-old company, which has a market value of £2.3bn.

The share sale comes as Rightmove is facing increasing competition from its main rival Zoopla – which is planning to float on the stockmarket next month – and estate agents setting up their own property portal.

Zoopla, which is just six years old and includes the websites Zoopla.co.uk and Primelocation.com, last week confirmed its intention to press ahead with a £1bn London flotation in June.

The float could value Zoopla founder Alex Chesterman's stake at more than £80m. It will be Chesterman's second big windfall after the sale of Lovefilm, which he cofounded, to Amazon for £200m in 2011.

Daily Mail publisher the Daily Mail and General Trust (DMGT), which owns 52% of Zoopla, will also make a big return on its investment.

Rightmove is also under increasing pressure from estate agents increasingly objecting to the fees to advertise on the website. The six biggest agents in London – Savills, Knight Frank, Chesterton Humberts, Strutt and Parker, Douglas & Gordon and Glentree Estates – are preparing to launch their own website, Agents' Mutual, next January.

More than 1,800 estate agents' offices have signed up to Agents' Mutual and the new portal has raised more than £5m in seed capital from members. Agents already signed up account for 12% of properties on the market, and those representing a further 19% have expressed interest.

Agents' Mutual, which is run by PrimeLocation founder Ian Springett, will ban participating agents from advertising their properties on more than one of the other big websites, meaning agents must choose between Zoopla and Rightmove.

"Our site will be the first portal fully owned by agents – this will always be the case – and it will become a serious competitor to the sites already in existence," Springett said. "The site will not be driven by the need to maximise financial returns to shareholders – which has driven up listing fees for agents and consumers on some other sites – but instead to create the best high-quality property search service."

Zoopla has offered agents shares in the company's flotation at a 20% discount to persuade them to stay loyal to the firm.

Fears about the health of the property market were raised yesterday by figures from the British Bankers' Association (BBA) showing the number of mortgage approvals dropped for the third month running. The number of new loans approved by high street banks in April fell to 42,173, from 45,045 in March.

Rightmove declined to explain why Forbes sold the shares, but he is understood to be in the process of buying a new house in South Kensington. It is the second time in recent months that Forbes has sold a lot of shares. In November he sold 138,729 bonus shares for £3.1m. Rightmove chief executive Nick McKittrick sold £6.1m worth in October.

Rightmove's shares, which have fallen by 15% so far this year, closed down 6p to £23.25. The shares are still worth seven times the 335p they floated at in 2006.