More than a thousand agents have joined the portal since the acquisition adding 57,000 listings while total monthly leads to agents have shot up 81%.

Edward Mellor has adopted a dual portal listing policy consisting of Rightmove and OnTheMarket only.

The portal suffers one of the biggest drops on the Stock Market after JP Morgan advises shareholders to release their holdings.

The portal's CEO Johan Svanstrom says its revenue and profit figures are healthy despite the anticipated attack from OnTheMarket and its new American owners.

Stone has set out seven key concerns with the CoStar deal as well as six potential solutions to try and resolve the situation amicably.