Sky News is reporting that Boomin, the portal founded by Purplebricks creator Michael Bruce, is close to finalising a new round of funding that will value it at almost £150m.
If true, that valuation would be substantially more than the current market capitalisation of OnTheMarket.
Bruce launched Boomin almost exactly a year ago, since when its agency membership and numbers of visits from consumers have been kept under wraps.
Sky says: "City sources said [Boomin] ... was likely to announce details of the fundraising - which has been overseen by Oakley Advisory - in the coming weeks. As part of the round, estate agents who sign up to the portal are being offered an allocation from a pot of free shares. Existing investors, including Channel 4's media-for-equity venture and Foxtons, are understood to be participating in the latest raise."
Officially, Boomin has some 8,000 agents on its platform but this is widely believed to have been a figure amassed because of free membership which comes to a halt tomorrow, April 1.
Boomin says it will reveal at least some information on paid-for agency membership next week.
Boomin has told Estate Agent Today it will not be commenting on the Sky News funding story.