The London Stock Exchange is reporting a nine per cent slide in third quarter revenue as competition from rival execution venues intensifies.
Revenue for the quarter dropped to £154.9 million from £169.4 million in the year ago period, although still ahead of analyst estimates of £149.9 million.
Presenting the results, LSE chief Xavier Rolet says: "Market conditions are expected to remain testing in the current quarter.
"We continue to focus on improving the shape of the business, with actions clearly underway to reduce underlying operational costs, and improve business efficiency and our competitive position."
The results presentation comes a day after the release of trading data from the rival Bats Exchange which clearly demonstrates the advances made by nimble multilateral trading facilities in stealing stock market share from incumbent venues.
The chief beneficiary is Chi-X, which now commands 24% of trading in FTSE100 stocks and on Tuesday surged ahead of Nyse Euronext to become the number two exchange across Europe measured by trading volumes.
The LSE has sought to fight back by taking a controlling interest in the bank-backed Turquoise franchise, and by expanding into post-trade services.
Despite these efforts, the LSE's clearing revenue for the quarter dropped by 13% due to a fall-off in interest earned on margin payments from trading firms.
There was better news from the information and technology services division, where a first-time contribution from newly-acquired MillenniumIT lifted revenue by three per cent.