Add janitors to the list of disgruntled employees on the Microsoft campus. But this time the company doesn't appear to be to blame.

Janitors who work at Microsoft as employees of SBM Site Services are protesting cutbacks by the subcontractor, saying their workload has increased substantially as a result of recent layoffs in their ranks. An SBM spokeswoman says the cuts are necessary, given the economic downturn, but adds that they aren't as deep as some of the workers are suggesting.

The workers, members of the Service Employees International Union Local 6, staged an intial protest on Friday and are holding follow-up events on the Microsoft campus this week, handing out leaflets and holding banners in opposition to the cuts. The workers say the previous subcontractor, ABM, employed about 359 workers to handle a variety of janitorial tasks across the Microsoft campus.

When SBM took over the operations late last year, the workers say, the numbers was reduced by 50 to about 309. Since then, further layoffs have cut even more people, they say. One worker, Dirk Koteles, estimates that the total is now down to about 250.

Not so, says Jessica Berg, a spokeswoman for SBM in San Francisco. She declined to address the apparent employment reduction from when ABM had the contract, but she says that only 10 people have been laid off since SBM took over, bringing the total to about 300 people. She said the SBM initially tried to coordinate the layoffs with the SEIU, but she said the union chose not to participate.

"SBM is commited to maximizing its efficiencies in order to ensure the long-term viability of service to its customers," Berg said, adding that further layoffs aren't currently expected but that some cuts were necessary given the economic environment.

It's the second protest on Microsoft's campus in recent weeks. Many engineers, testers and other technical workers on contract assignments at Microsoft have seen their pay cut by 10 percent as a result of the company's decision to reduce the rate it pays the temporary agencies that employ them.

However, in this case, the subcontractor appears to have acted on its own. Microsoft referred inquiries to SBM.

The workers say they plan to continue protesting throughout the week.

[Flickr Photo: Steve Longus.]