GoCompare today shut down a takeover bid from Zoopla Property Group (ZPG), which it said was "highly opportunistic" and undervalued the company.
The comparison website said this afternoon that it had received an unsolicited approach from ZPG last week.
ZPG valued GoCompare at 110p per share, more than £400m. The offer represented a 16 per cent premium on the closing price of the insurance comparison site the day before the proposal.
After Sky News reported the takeover offer, GoCompare's share price jumped 10 per cent to 102p.
In a statement, Sir Peter Wood, chairman of GoCompare, said: "The board and I are extremely pleased with the transformation of the business that the management team has delivered since the demerger.
"ZPG's proposal is highly opportunistic and fundamentally undervalues the company and its prospects."
GoCompare demerged from esure group in November last year, and said today that it had made significant progress since then. The firm has invested in its software and digital marketing, and posted better-than-expected results for the first half of the year.
The company has also made its first strategic investments, in Mortgage Gym and Souqalmal.com.