Companies also use Contributor License Agreements
and similar legalese(ToS/User Agreement/Company Code of Conduct) to confine their "open source" code
into some semi-commercial/proprietary components and
"public components": the code is nominally open, but dealing with it
requires accepting the terms of the company hosting it.
Even companies doing it in the open, on Github have
the guts to claim they're champions of open source.