U.S. District Judge Thomas Penfield Jackson will issue the findings at 3:30 p.m. PT, Microsoft said.
Jackson's findings of fact are not a ruling and are only the first stop on a long legal road that could ultimately lead to the Supreme Court.
In the case, the Justice Department and 19 states allege Microsoft used its Windows monopoly muscle to crush Web browser rival Netscape Communications, now owned by America Online. That timing has some antitrust attorneys speculating that the findings of fact may go badly for Microsoft. (See related story.)