Aircraft maker Airbus (search) insisted on Thursday it had no intention of taking sides in a Microsoft (MSFT) antitrust case, even though it filed a brief in an EU court on the software giant's side.

"We are following the legal procedures to get clarification (of a technical point), but the intention is not to take sides," an Airbus spokeswoman said. "We are not taking sides."

A court spokesman said the only way it would be possible for a company to file was to take sides. The Airbus action won praise from Microsoft and criticism from its opponent, the European Commission.

"If you intervons about the text."

In March the Commission found that Microsoft had abused its dominance of PC operating systems and ordered it to make changes to create a more level playing field for rivals. Microsoft also paid a record fine of 497 million euros ($604.9 million).

Microsoft appealed the EU ruling and asked the Court of First Instance to suspend the sanctions until the case is completed, probably three or more years from now.

In a statement, Microsoft welcomed Airbus's comments and said its filing "confirms that, as Microsoft has said all along, the negative effects of the Commission's decision will be felt well beyond the software industry."

But a spokeswoman for the European Union (search) executive disagreed, saing the Commission was surprised about the Airbus intervention and sceptical of its arguments.

Some close to the case characterised the Airbus filing as an argument that the Microsoft case might spill over into its business, making it more difficult for Airbus to innovate.

"We fail to see how the Microsoft decision could affect Airbus," said Amelia Torres. "The decision is specific to Microsoft, to the software market and to Microsoft's behavior."

Microsoft's request for a suspension of sanctions will be heard by the EU court on Sept. 30.