Pun may have come T-shirts, but technically, "The Punisher" is a Marvel Comics character.
Technically, the stylized 'skull' is a Marvel Comics Group registered trademark. If Marvel wanted to pick nits, they could easily issue a "cease and desist" order for Pun to stop using the logo. They'd have a harder time with the name, of course, but they'd have a definite case considering the use of the name and the logo.
Not that I think Big 'Ol Marvel wants to come down and whang a nail in Pun's biz, but it does illustrate how you need to be a little selective when coming up with a logo and naming a fledgeling business.
Now, to reveal my comic-book-geekdom; The Punisher, who's real name is Frank Castle, was a typical ex-special-forces/Ranger/green beret/delta force/seal Vietnam veteran enjoying his new civilian life with his wife and kid on a picnic in New York's Central Park, when they happened to accidentally witness a mob hit.
The baddies then gunned down the family, and only Frank survived. In standard Marvel (tm) fashion, he then embarked on a lifelong mission to eradicate baddies and druggies.
He made a costume, found some guns, and started calling himself the Punisher- IE, he was punishing the bad guys.
He was a minor character way back when, little more than a gun-toting thug to give some storyline balance from the "super powered" villains. But with the late eighties' and early nineties' slide towards the "bad good guy" (Wolverine, for example- another "misunderstood killer") Pun became more of an anti-hero. You identified with the character even if his activities would have branded him a "villain".
So nowadays- according to books called "The Punisher's Armory" (which aren't so much books as 'catalogs') Pun has damn near every weapon you can think of. Gatlings, land and claymore mines, personal helicopters, an endless supply of ammo and explosives, electronic surveillance equipment, armored vans and cars, lots of hidey holes all through New York, and lots and lots of money (which he takes from drug dealers in order to buy all this cool stuff.)
Unfortunately, I haven't had the time or wherewithal to collect comics as I used to, in about eight or nine years. Few places locally even carry comics anymore, and those they do are usually all Archie or some Pokemon crap. But I still have about 2,500 boxed up somewhere... a few date back to the seventies'.