The Redmond, Wash., company said Monday it is making the "Sender ID Framework" available under its Open Specification Promise program. That means Microsoft will not sue anyone who creates products or services based on the e-mail technology.
The move is part of an effort to promote interoperability among commercial and open-source software products, and among Internet access providers that utilize e-mail authentication, Microsoft said in a statement.
"Users will be able to implement, commercialize and modify Microsoft's patented e-mail authentication technology without having to sign a licensing agreement," it said.
Sender ID is a caller ID-like system for e-mail meant to help fight spam and related cyberscams such as phishing. Microsoft has been pushing the technology for a couple of years as a partial solution to junk e-mail. Intellectual property issues around the technology have flared up in the past as a roadblock to adoption.
Microsoft announced the OSP in September, when it said 38 Web services specifications would be available under the promise. Earlier this month, it was expanded to include the Virtual Hard Disk Image Format specification.
Nearly two years after Sender ID's launch, 36 percent of all legitimate e-mail sent worldwide uses the technology, via about 5 million domains, according to Microsoft data.
