That is, it's not just that you must preserve the copyright and license on the code, you must make extra effort to reproduce it when making binary distributions of it.
I learned about this by a request from an author of a BSD-licensed library, who asked why Chrome didn't include his name in its credits. (Ironically, I had initially suggested we avoid using this library due to its historically aggressively advertising license, only to embarrass myself because it no longer used that license. I was wrong at that time since the old license no longer applied, but in the end I was kind of right!)
PS: check out about:credits in Chrome and expand the "webkit" section. We actually have to list every contributor by name. Now that I look I bet that list is out of date. :(