The London Metal Exchange (LME) says it has received "several expressions of interest" that could lead to a takeover. CME Group, IntercontinentalExchange and SGX are all said to be in the running.
In a statement, the 130-year-old bourse says its board will now "begin a formal process which may or may not lead to an acceptable offer for the company being received".
The exchange's members, who own it, think it could be worth more than £1 billion, according to the Financial Times.
Although the LME has refused to name its suitors, CME Group, ICE and Singapore's SGX, which all offer metals trading on a smaller scale than the target, are being widely reported as the most likely bidders.