A big thanks to Johan Marien from Microsoft for addressing some of the recent licensing questions raised over the WDK samples’ EULA. According to Johan, the license restrictions on redistribution of WDK source were present in the SP1 DDK, and the samples.txt file was added to provide a mechanism for making certain source code redistributable in the future.
His post on NTFSD has all of the details, which I won’t repeat here. He also asks for feedback on which samples you would like to see made available for redistribution, so if you have a business need, it may be worth bringing it up with him. Otherwise, it looks like you shouldn’t distribute source code derived from WDK samples to customers, unless you have a separate agreement with Microsoft.
[...] Speaking of which, I mailed Johan Marien at Microsoft today to let him know that I think the Passthru sample should be made redistributiable, since so many IM drivers are based on it directly. If you agree, you might want to drop him a note in support. Or, leave a comment here and I’ll forward everything on to him. [...]