I have some files in my project that started from a sample in the all-in-one code sample browser: http://visualstudiogallery.msdn.microsoft.com/4934b087-e6cc-44dd-b992-a71f00a2a6df Some files contain boilerplate code that I modify heavily. They contain MS comments at the top that mention the license, copyright microsoft etc. Am I required to leave the entire comment block at the top of the source files that I modify or is it okay to just include the MS-PL license in a separate file for the whole project?