Rules just exist as text in the ruleset already though, but I get what you mean. Maybe have them “not grant any formal obligations/abilities.”

Other potential phrasings:

“Special Case Rules that are unactive shall be interpreted as having no effect.”
“Special Case Rules that are unactive shall be interpreted as if they were not in the ruleset.”
“If an unactive Special Case Rule would allow or forbid an action, or have an effect on a Prince or the gamestate, instead it does not.”

Also, shouldn’t it be “inactive”, rather than “unactive”?

This is not a proposal, and it is too late to become one.

unactive was carefully and deliberately misspelled.

to avoid conflicts with the word “inactive”

“Special Case Rules that are unactive shall be interpreted as having no effect.” It can’t be all of the gamestate, since they clearly occupy the ruleset, which is part of the gamestate; setting a rule to unactive would simply allow anyone to remove it from the ruleset.

“Special Case Rules that are unactive shall be interpreted as if they were not in the ruleset.”
This would make it difficult if people wanted to edit an unactive rule. Suppose an unactive rule was badly worded, it shouldn’t have to be active to fix the text. I’m not sure if an unactive rule would even be able to be set to active, since unactive rules are interpreted as not existing.

Agreed that “not in the ruleset” doesn’t work, for the reasons you say.

Interesting point that the Ruleset is Gamestate. This wasn’t immediately obvious to me, but the definition of Gamestate in the appendix is “Any information which the Ruleset regulates the alteration of”, which would definitely include the Ruleset itself.

What conflicts with the word “inactive”? The ruleset doesn’t use “inactive”.

No but it’s not unheard of for it to be used in dynastic rules https://wiki.blognomic.com/index.php?search=inactive&title=Special:Search

I think we’d avoid using the word dynastically if it was used elsewhere. (And all those rules also use the word “active” as well.)

The existing text is actually quite robust. Other than the part where I think “special case” is an inaccurate name.