June 8 (Bloomberg) -- European Union regulators asked personal computer makers whether Microsoft Corp. pressured them to oppose an EU plan to give consumers a choice between Internet browsers on new PCs, people familiar with the case said.

The European Commission in Brussels sent questionnaires to PC makers asking about their communications with Microsoft, according to two people who have seen the queries and declined to be identified because the document is confidential.

The commission in January filed a complaint accusing Microsoft of possibly harming consumer choice and product innovation by including the Internet Explorer browser with its Windows operating system. Microsoft may be forced to disable some software code and offer PC users a choice of browsers when setting up a new PC on a so-called “ballot screen,” the company said in a U.S. regulatory filing on Jan. 18.

Microsoft has been under investigation for tying the browser to Windows for a year and a half. The case adds to years of wrangling between Microsoft and the commission, which previously ruled the company illegally withheld network data from rivals and bundled a media player with Windows.

Microsoft hasn’t seen the commission’s questionnaire and doesn’t pressure any PC makers to oppose the ballot-screen remedy, said Jesse Verstraete, the company’s spokesman in Brussels. Commission spokesman Jonathan Todd said the regulator has an antitrust case under way. He had no comment about the questionnaires.

Microsoft, based in Redmond, Washington, fell 9 cents to $22.05 at 4 p.m. New York time on the Nasdaq Stock Market. The shares have gained 13 percent this year.

EU Questions

Three of the eight questions focus on the relationship between Microsoft and PC makers, the people said. The commission is seeking to determine whether Microsoft asked companies to make any specific statements to regulators, according to the people.

The remainder of the questions ask PC makers and rival browser makers to comment on the EU’s proposed ballot screen solution. The commission is seeking information on what browsers should be included, what criteria should be used to add a browser and how the browsers should be presented on the ballot screen, the people said.

“We’re hearing from our computer manufacturer partners that they have serious concerns about the financial and operational impact of the ballot screen remedy, which is being promoted by some of our competitors,” Microsoft said in a statement. “We have encouraged them to share their concerns with the commission.”

No questions were asked about forcing PC makers to pre- install browsers on their products, the people said.

To contact the reporter on this story: Matthew Newman in Brussels at Mnewman6@bloomberg.net

Last Updated: June 8, 2009 17:00 EDT