Singapore's intellectual property watchdog has handed down a ruling in a dispute over trademarks between two major American operators of market exchanges.

Chicago Mercantile Exchange (CME) applied to invalidate Intercontinental Exchange Holdings' (ICE) trademark registrations of the words "Brent" and "Brent Index", which refer to a global benchmark for oil prices.

ICE registered these in 2015 for a range of financial services.

CME argued that those words, used in relation to financial services, do not have the distinctive character required of a trademark and are commonly used terms in the practices of those who trade or deal with financial derivatives.

ICE responded that it is the sole provider of Brent pricing information and has been regulated in doing so by Britain's Financial Conduct Authority since April 1, 2015.

The Intellectual Property Office of Singapore ruled yesterday that ICE's trademark registrations for "Brent" and "Brent index" were invalid.

Adjudicator David Llewelyn said much as ICE may repeat that it is the sole provider of Brent pricing information, this "does not lead inexorably to the conclusion that 'Brent' is a registrable trademark or, if registered, is validly so".

"Other honest traders are likely to want to use the words 'Brent' and 'Brent Index', and should not be forced to rely on a defence under the Trade Marks Act in order to do so," he added.

CME is part of CME Group, which owns and operates large derivatives and futures exchanges in Chicago and New York. ICE is a Fortune 500 company operating a number of exchanges such as the New York Stock Exchange and ICE Futures Europe. They are seen in the industry as the world's two largest energy exchanges and close competitors.