As somebody who has worked at research institutes in the US, this comes up a lot. Some companies say that an academic user must have an e-mail address ending in ".edu" (which in the US means a school or university), but others define it more broadly to include non-profit research institutes as well. It gets murky because many research institutes actually have grad students doing their projects there (even if they are officially enrolled at a university elsewhere).
It seems to me that CERN is a research institute but whether that is counted as an academic institution, from a licensing POV, is a different question