Microsoft's legal team has claimed that Google lied about the security status of its Apps for Government platform after recent court documents were released.
Google has been locked in a year-long legal battle for the right to bid for US government cloud contracts, after being excluded from a deal to service 88,000 Department of the Interior desktops.
Court documents released in the case show that Microsoft claims that the Apps for Government platform failed to meet the standards set by the Federal Information Security Management Act (FISMA), a key point in Google's case.
"Open competition should involve accurate competition. It's time for Google to stop telling governments something that is not true," said David Howard, Microsoft's deputy general counsel, in a blog post.
Microsoft's claim comes from documents showing that Google's Apps Premier package did meet FISMA standards, but that the Apps for Government package did not. Microsoft called for Google to be more open in acknowledging the security failings of its cloud platform.
However Google hit back strongly, pointing out that Microsoft's claim is outdated and that Google has already addressed the government's security concerns.
David Mihalchik, head of strategy and business development for Google's federal enterprise team, told V3.co.uk in a statement that Microsoft's claims are bizarre, since Microsoft's own offering had also not received a similar security clearance.
"This case is about the Department of the Interior limiting its proposal to one product that isn't even FISMA certified, so this question is unrelated to our request that the department allow for a true competition when selecting its technology providers," he said.
"Google Apps received a FISMA security authorisation from the General Services Administration in July 2010. Google Apps for Government is the same system with enhanced security controls that go beyond FISMA requirements. As planned we're working with the GSA to continuously update our documentation with these and other additional enhancements."
Google and Microsoft are competing for the provisioning of cloud services to government as states seek to reduce costs by eliminating on-premises software. Microsoft has a huge base in the government sector around the world and is keen to defend its market share.
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