The London Stock Exchange (LSE), which has fended off a series of possible suitors, has seen profits jump sharply during the six months to 30 September.
Stock markets are proving to be attractive investments
Operating profits rose 60% to £81.3m ($155m), helped by more firms listing and growth in electronic trading.
The US tech-based Nasdaq index has acquired a quarter stake in the LSE after its $4.2bn takeover was rejected.
UK-based broker Icap has also held talks, but the LSE has said that it can continue to grow alone.
"Our coveted global brand and our unique strategic position at the heart of the world's capital market in London make us an exceptionally valuable asset," the LSE said in its results statement.
"We are continuing to assess opportunities for further value accretion from this very strong base."
Pre-tax profits at the exchange were up to £76.7m, from £29.4m in the same period last year.
Nasdaq, whose approach was rebuffed in March, would have to pay at least £12.43 a share if it wanted to launch a fresh bid, the top price it paid to acquire its stake.
Pan-European market Euronext and Germany's Deutsche Boerse have also made approaches to the LSE.
Earlier this year, LSE chief executive Clara Furse said that the company would not do a deal for the sake of it.
However, analysts and market observers have speculated that stock exchanges will need to merge if they wanted to keep on growing and offer a wide-range of global financial services.
The New York Stock Exchange has agreed to merge with European market Euronext, and analysts are expecting further tie-ups in the industry.
The LSE is attractive because of the UK's light-touch regulatory regime that makes it less onerous for companies to list their shares.