I came across a library on githubGitHub (now Zlib/Libpng licensed) that is a fork of a library that was originally released under the Boost software license. The question I have is, is
Is it legitimate/legal to relicense boost software under the zlib license?
I guess the Boost license doesn't explicitly deny nor explicitly allow relicensing as far as I can tell, so I thought it was worth a question.