In Pennsylvania, you don't even need a permit to carry open... QUOTE]
http://www.atf.gov/firearms/statelaws/25thedition/index.htm
read the text in 6106, which makes concealed carry of a "firearm" (handgun, or sbs/sbr) without a liscense a 3rd degree felony, or a misdemeanor if there is no reason not to issue liscense if applied for.
6109a specifies that the liscense is good only for carrying concealed. 6109e reiterates the concealed carry provision.
of course, hunters engaged in sport or traveling to sport are excepted in carry of a handgun under the sportsmen's permit, 6106c, if they apply for it.
someone you lend you car to is also immune from prosecution if you gun is found in the car while they are operating, and if they are otherwise eligible to apply for permit.
6106 subsection 11, interestingly, enables permit holders of all states to carry while in their vehicle (as in transit).
what i do not see is language controlling open carry, except with regard to philadelphia under 6108.
i always assumed penna was concealed only, but under the strict interpretation of the statute, it appears that open carry is only prohibited in philadelphia. of course, if a cop wanted to make your day uncomfortable, there are other laws to apply, i'm sure.