Yea folding knives laws are often per city/county too. In Washington state it ranges 3-3.5” folding knives. Fixed as far as a understand are illegal (here). Also anything deemed a “dangerous” knife or something (here). Probably giving some leniency for legal interpretation. Some places around the country/world are far more relaxed, some far more draconian.
Also most states have places forbidding weapons of any kind...federal buildings, airports, schools, malls, certain places of employment, etc.
I’m a stickler for the letter of the law, just a nerd etc :). Good to have a few knives for various situations and locations. While camping an easy case could made for you carrying even a huge fixed blade let alone a Tenacious. You have to process more wood and food while near a campfire than in the break room at work.