Red Hat general counsel Mark Webbink told vnunet.com that the changes went into effect on 3 November. The company did not advertise the change because it believes that offering Linux indemnification "is not a big deal".
Linux indemnification has been a major concern in the open source community after SCO claimed that it owned the intellectual property of the Linux and Unix operating systems and demanded that users paid licence fees.
Microsoft is generally seen as the biggest threat to open source because the company faces the largest impact on its proprietary software from open source alternatives.
Indemnification means that a vendor promises to pay for any legal expenses and judgements as a result of patent claims. Red Hat did not previously protect its customers against any claims.
Red Hat added the indemnification to its Open Source Assurances programme designed to let companies use open source software without interruptions because of legal issues.
It promises to replace infringing code or modify its software to prevent infringement. Alternatively the company promises to obtain the rights to allow companies to continue to use the software.
Red Hat said that it would provide additional information on the changes at a later time.
Despite Red Hat's claim that the indemnification "is not a big deal," the company's hand was forced, argued Raven Zachary, an open source analyst with The 451 Group.
Microsoft and Novell unveiled their partnership on 2 November. A week earlier, Oracle announceed that it would start offering support and indemnification services for users of the Red Hat Enterprise Linux distribution.
"The winners here are the Linux customers," Zachary told vnunet.com. "Now you have three providers of indemnified Linux in the market."
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