By Natalia Drozdiak

BRUSSELS -- In a bid to win European Union antitrust approval of its $26 billion acquisition of LinkedIn Corp., Microsoft Corp. has proposed concessions that would allow rival professional social networks access to its Outlook programs, according to people familiar with the matter.

After the merger, the people said, rival networks would have access to Microsoft's Outlook add-ins program -- which allows third-party tools to integrate with Outlook -- and Outlook APIs -- or application programming interface, which allows discrete programs to communicate with one another. Some of the networks already have access to those Outlook programs, they added.

Microsoft's Outlook offers email and calendar management.

Among other things, the measures proposed by Microsoft would allow for the display of profiles from other sites besides LinkedIn, such as German business-professionals network XING, in an Outlook calendar entry of a meeting between two or more people.

In addition, Microsoft has pledged to allow computer manufacturers such as Dell Inc. and Hewlett Packard Enterprise Co. to disable the LinkedIn shortcut on desktop devices, the people said. In an earlier EU review, Microsoft had to take steps after antitrust regulators in 2004 condemned it for bundling products into its Windows software.

None of the remedies, however, would offer rivals direct access to LinkedIn's pool of data -- a condition Salesforce.com Inc., which lost out to Microsoft in bidding for LinkedIn, has pressed for publicly. No outside entity currently has unlimited access to LinkedIn's data trove.

Microsoft announced its deal with LinkedIn in June and aims to close the transaction this year. Regulators in the U.S., Canada, and Brazil have cleared the acquisition.

The European Commission, the bloc's antitrust regulator, has sought comment from rivals after Microsoft submitted the concessions on the acquisition last week. Following the submission, the EU extended its deadline to Dec. 6 to complete its review of the merger. That could be extended further if the regulator still has concerns about the deal and decides to open an in-depth investigation.

The EU's antitrust authority, which has said it would scrutinize mergers involving large amounts of data more closely, sent out questionnaires to rivals in October posing questions about the rough value of LinkedIn's data and whether rival sites can replicate it.

Microsoft has argued that much of the user data on LinkedIn is also available on other social-media sites, such as Facebook Inc., and that Facebook in particular should be considered as part of the same market in the EU's review process.

However, Salesforce continues to press for regulatory scrutiny. "We believe this deal raises significant antitrust and data privacy issues," said Burke Norton, Salesforce's chief legal officer.

Mr. Norton wrote in an October blog post that the issue is not whether Microsoft allows other service providers to integrate their offerings with its products and services, but "the much richer and irreproducible interactivity data, or metadata, to which Microsoft alone will have access." Microsoft's exclusive access to that information, Salesforce contends, will confer an unfair advantage over competitors.

--Rachael King contributed to this article.

Write to NataliaDrozdiak at natalia.drozdiak@wsj.com

(END) Dow Jones Newswires

November 22, 2016 13:28 ET (18:28 GMT)

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