Microsoft has offered concessions to EU antitrust regulators over its $26 billion bid for social network LinkedIn, the European Commission said yesterday, as the US software company seeks to allay concerns over its largest ever deal.

The move came after the EU competition enforcer expressed concerns about the deal at a meeting with Microsoft executives last week.

The Commission, which will rule on the deal by December 6, did not provide details. It is expected to seek feedback from rivals and customers before deciding whether to accept the concessions, demand more or open a full investigation.

Microsoft sees competition from social network Facebook and wants regulators to take that into account

Microsoft declined to comment. The LinkedIn acquisition will allow it to add a suite of sales, marketing and recruiting services to its core business products as it gears up for next-generation computing.

LinkedIn makes most of its $3 billion annual revenue from job hunters and recruiters who pay a monthly fee to post resumes and connect with people.

US rival Salesforce, which lost out on the bidding for LinkedIn, has warned of the threat to innovation and competition and urged regulators to examine the antitrust and data privacy issues thoroughly before clearing the deal.

Microsoft, however, sees competition from social network Facebook and wants regulators to take that into account, people familiar with the matter said.