Chi-X released a statement admitting an enquiry has been received but would not be drawn on who the bidder was.
Pan-European stock market BATS was touted as a potential suitor yesterday. The firm declined to comment but City A.M. understands it is not the source of the enquiry.
Other likely suitors include Nasdaq and Deutsche Börse, both of whom are said to be eager to consolidate given tough market conditions.
An industry source told City A.M.: “What the market will be looking out for is interest from other sources now someone has broken cover.
“Volumes are anaemic and it is difficult for exchanges to make a profit. The LSE has already consolidated with its acquisition of Turquoise and could face competition issues if it bid for Chi-X. Nasdaq is a more likely rival bidder as it doesn’t have a presence in Europe at the moment.”
Chi-X, which says it has made an operating profit for the last seven months, was set up in 2007 to rival the LSE.