they didn't change gas stove

to replace gas stove, no need permit I think.

some place may need license plumber- this have to ask around your township (or wait for people to complain.

once I thought loews has appliances replacement promotion, where they take out old, install new for free or some small fee. so it must be, in general, gas stove replacement no need permit/license.

note: relocate is different. relocate most likely need inspection, since it involves roughing work