The US Senate Judiciary Committee will look into accusations by Mozilla that Microsoft is restricting access to important programming tools for browsers that will run in Windows RT, a political blog reported last week.
The Hill cited unnamed aides to Democrat Senator Herb Kohl, the chairman of the Subcommittee on Antitrust, Competition Policy, and Consumer Rights, as the source for its report.
Last week, Mozilla, the maker of Firefox, said Microsoft was withholding access to APIs - application programming interfaces - that Mozilla considers crucial for building a browser that can compete with Microsoft's own Internet Explorer 10 on ARM devices.
In a blog post last week, Harvey Anderson, Mozilla's chief counsel, raised the antitrust flag, saying that Microsoft's blocking of the APIs "seems to represent the very behaviour the Department of Justice-Microsoft settlement sought to prohibit."
Microsoft is no longer under US government scrutiny in the wake of the landmark 1998 antitrust case, but the eventual settlement required Microsoft to share its APIs with third-party vendors. Microsoft has repeatedly promised to continue that sharing.
In answer to follow-up questions last week, however, Anderson seemed to back away from any legal recourse. "We think the most effective way to resolve this is through critical discussion and transparency of the issues rather than through legal action," he said.
Google has said it shares Mozilla's concern over the Windows RT browser situation.
Microsoft has declined to comment on Mozilla's accusations.
Kohl's office was unavailable for comment yesterday.