Rightmove has proved a stock market winner for a fund manager who calls it a “mission critical” tool for estate agents.

James Thornton, who manages the Rathbone Global Opportunities fund, said agents would turn the lights off before giving up Rightmove.

Featured in yesterday’s Mail, writer Sally Hamilton said of Thornton: “His aim is to pick stock market winners whatever their business and wherever they are in the world, and Rightmove makes the grade.”

Hamilton says that given housing market conditions, it “might seem reckless” right now to back such a business.

She continues: “But Rightmove has an advantage – it is the largest online portal used by 80% of Britain’s estate agents.”

The tougher the market gets, “the more help these agents will need – and will upgrade their packages with the website, or so it hopes”.

Thornton himself says: “Estate agents will need to pedal harder to sell homes.

“Rightmove is a mission critical tool for them.

“They are more likely to turn the lights off before giving up their Rightmove subscription.”

Rightmove has been one of the fund’s best performing stocks, with its share price jumping about 1,500% since the stock was purchased in 2009.