NEW: the package fedora-license-data now contains BNF grammar which you can use. It is available in `/usr/share/fedora-license-data/grammar.lark`

You'll have to explain to me the significance of this. 

This is good starting point:

  https://en.wikipedia.org/wiki/Backus%E2%80%93Naur_form

The BNF is one of the basic grammar used in formal automata. It is the data part of any formal validation or compiler. The validation is most relevant in this case.

There is lot of libraries that load the grammar and validate or tranform the input. 

I wrote this grammar for Lark library. The validation is then just two-liner

You can see it used e.g., here

  https://pagure.io/copr/license-validate/blob/main/f/license-validate.py#_31

Miroslav