Thomson Reuters, which has proposed a number of changes to the financial codes in its feeds in response to competition concerns, has been informed by Europe's top antitrust official that the modifications are not enough.

EU competition commissioner Joaquin Almunia said that following market testing, he was unconvinced that Thomson Reuters was making it easy enough for customers to use alternative providers. The long-running competition case had now reached "a critical stage", he said.

The case concerns Reuters Investment Codes (RICs), which are alphanumerical codes used by the company and its customers within their data feeds to identify, navigate and retrieve a structured set of data.

The EU is investigating whether customers are effectively 'locked in' to Thomson Reuters RICs because of the potential costs of rewriting software if they need to connect to other data feeds in a complex market.

But Thomson Reuters recently proposed a number of concessions to permit clients additional usage rights for the RICs, and to assist them in mapping RICs to rival sources.

Thomson Reuters said in a statement to Computerworld UK that it was "analysing" the EU feedback.

"While we are undergoing this review, it would be inappropriate to comment," said a spokesperson. "However, Thomson Reuters will continue to fully cooperate with the EU while it is engaged in this process."

In other Thomson Reuters news, on Monday the company announced a major upgrade to its market feeds by adding analysis of content from social media sites.

The Machine Readable News service now delivers traders with analytics from 50,000 news sites and four million social networks, in a format promised to be digestible and to highlight the key information.

Analytics include sentiment, relevance and novelty indicators that capture market opinion, for algorithmic trading systems as well as risk management and human decision support processes. Thomson Reuters said the development would help traders to be better informed as they shape their strategies.