Microsoft has joined with Puget Sound Energy and the law firm of Perkins Coie to support Referendum 71, an effort to expand rights to same-sex partners in Washington. The Puget Sound Business Journal reports that Microsoft recently donated $100,000 to Washington Families Standing Together, the group leading the charge to pass the referendum.

That makes Microsoft the largest contributor to the pro Referendum 71 efforts, which has raised a total of $780,000, according to the PSBJ. Meanwhile, Protect Marriage Washington, which opposes the referendum, has raised about $60,000 in cash and in-kind contributions.

The public disclosure filing can be found here. And here's what The Slog has to say about Microsoft's involvement in the campaign to pass R-71:

"Microsoft's brazen role in R-71 will outrage the Ken Hutchersons of the world, who pressured Microsoft for years to back off from supporting gay-rights legislation. And it could also summon conservative interests—e.g., the Mormon Church—to dump money in on the other side. After October 12, state rules block any person or group from donating more than $5,000 to the campaign."