IBM (NYSE: IBM) has offered to make it easier for competitors to get spare parts for its mainframe computers in an attempt to get European regulators to close an antitrust probe.

The European Commission in Brussels opened an investigation into whether IBM was abusing its dominant position in the market for mainframe computers in July 2010, focusing on profitable maintenance services.

Reuters reported that a preliminary finding showed IBM’s practices “may amount to a constructive refusal to supply these inputs (required for the maintenance of IBM mainframe hardware and software),” the Commission said in a statement Tuesday.

“IBM does not agree with the Commission’s preliminary assessment. It has nevertheless offered commitments… to meet the Commission’s competition concerns,” the EU’s executive Commission added, according to Reuters..

Mainframes are powerful computers that are used mostly by big companies and governments.

IBM said it was offering the concessions even though it didn’t agree with the Commission’s initial assessment of a potential abuse of dominance.

“I commend IBM’s readiness to address our concerns about fair competition in the market for large computers which are crucial for the functioning of today’s economy,” the EU Commissioner for competition said in a statement as reported by The Wall Street Journal.

In a statement, IBM said it welcomed the decision to close the second investigation and “the proposed resolution of the Commission’s investigation of certain IBM mainframe maintenance practices.”

The Commission is now asking IBM’s competitors and customers to comment on the commitments to decide whether they are sufficient.

Mainframe sales make up a small portion of IBM’s revenue, but the company has been making a lot of money selling software and services linked to the hardware it produces.

The closing of the probe into whether IBM was unlawfully tying its mainframe hardware with its operating system will come as a relief to the 100-year-old company. That investigation was triggered by complaints from emulator software vendors T3 and Turbo Hercules, which were later joined by Neon Enterprise Software.

The Commission also said it was closing a separate probe into whether IBM was unfairly tying its mainframe hardware with its operating system.

T3, Turbo Hercules and Neon Enterprise Software filed complaints.

“The three complaints have been withdrawn,” the EU said.

IBM employs some 10,000 people at its campus in RTP.

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