An article in Cover Pages quotes Lawrence Rosen, an attorney and lecturer at Stanford Law School, as saying, "I'm pleased that this OSP is compatible with free and open-source licenses.
"[4]Linux vendor Red Hat's stance, as communicated by lawyer Mark Webbink in 2006, is: "Red Hat believes that the text of the OSP gives sufficient flexibility to implement the listed specifications in software licensed under free and open-source licenses.
In a published analysis of the promise it states that[8] "...it permits implementation under free software licenses so long as the resulting code isn't used freely.
In one it says, "we can't give anyone a legal opinion about how our language relates to the GPL or other OSS licenses".In another, it specifically only mentions the "developers, distributors, and users of Covered Implementations", so excluding downstream developers, distributors, and users of code later derived from these "Covered Implementations"[9] and it specifically does not mention which version of the GPL is addressed, leading some commentators to conclude that the current GPLv3 may be excluded.
The OSP provides the assurance that Microsoft will not assert its Necessary Claims against anyone who make, use, sell, offer for sale, import, or distribute any Covered Implementation under any type of development or distribution model, including the GPL.