Two former Microsoft employees have sued the Windows giant seeking compensation for the mental trauma of screening child sex abuse photos, murder videos, and other extreme content flowing through the company's online services.

Henry Soto and Greg Blauert were assigned to Microsoft's Online Safety Team, formed in 2008 following a federal requirement that unlawful material like child pornography must be reported to the National Center for Missing & Exploited Children (NCMEC).

Soto, according to the complaint, was transferred to the Online Safety Team involuntarily in 2008 and in the years that followed "was required to view many thousands of photographs and videos of the most horrible, inhumane, and disgusting content one can imagine."

The lawsuit's paperwork – filed at King County Superior Court in the US state of Washington last month and obtained by The Register today – can be found here [PDF].

Microsoft in an emailed statement said that it disagreed with the allegations and insisted that it takes seriously both its responsibility to remove and report imagery of child sexual abuse and the health and welfare of its employees.

"Microsoft applies industry-leading technology to help detect and classify illegal imagery of child abuse and exploitation that are shared by users on Microsoft Services," a company spokesperson said. "Once verified by a specially trained employee, the company removes the imagery, reports it to the National Center for Missing & Exploited Children, and bans the users who shared the imagery from our services."

Ben W Wells, the attorney representing Soto, in a phone interview with The Register explained that Microsoft reviews content listed in Bing and stored in OneDrive.

"That's where people store things and sometimes they store very inappropriate things," said Wells. "There are laws that require Microsoft, if they see something, to report it."

Soto and Blauert were among those responsible for flagging objectionable material. According to Wells, the Online Safety Team reviewed content forwarded by two contractors who handled initial content screening for Microsoft.

Microsoft declined to comment on its contracting arrangements, but pointed to its PhotoDNA service as a means by which content gets flagged for review.

Blauert began working for Microsoft contractor Society Consulting in 2011 doing content screening, the complaint says, and was hired by Microsoft in 2012 as a full-time employee doing the same work. He claimed disability in 2013.

Soto went on medical leave in 2015.

The Online Safety Team appears to have broad latitude to screen material and access to match. "In 2008, Mr Soto and others had 'God-like' status and could literally view any customer's communications at any time," the complaint states.

Microsoft declined to address this beyond reiterating that it disputes the claims.