* STATE CASE: A lawsuit in Minnesota alleges Microsoft overcharged about 1 million people or businesses in the state between 1994 and 2001. Microsoft has settled similar antitrust cases in nine states and Washington, D.C., for $1.5 billion.
* NATIONAL ANTITRUST CASE: Microsoft awaits a U.S. appeals court ruling on whether sanctions in the federal settlement were adequate. Massachusetts is pressing for tougher penalties.
* PRIVATE SUITS: Microsoft's Seattle-based rival RealNetworks Inc. has sued the company, alleging it illegally monopolized the field of digital media by including its Windows Media Player with its Windows operating system. Microsoft denies it.
* JAPANESE PROBE: In February, officials from Japan's fair trade watchdog raided Microsoft offices on suspicion of monopoly law violations--in particular, whether Microsoft attached overly restrictive conditions to deals with computer makers. Microsoft said it had already dropped a controversial provision of those contracts but was cooperating with authorities.
* LINUX: Governments and companies are increasingly eyeing the open-source operating system as a less expensive and more secure alternative to Windows.