Image was too small, is it a patent or a trademark?
I can understand it if it's a trademark, but a patent would be weird, unless it's on the process for marking the swirly shell.
If it is a patent, they last either 17 or 20 years, depending on when they were filed. Trademarks continue thanks to Disney for like forever, as long as you keep renewing them every 10 years.
**Reads some more** It does look like a trademark infringement. To be fair under trademark law, there's the premise of if you can get one product confused for the other. There's a run of redemption that DOES look a lot like the swirly pattern of Marberliser.
Pissing contest it may be, but trademark lawyers are expensive, I'd probably do the same thing. Trademark law has no criminal component, so if he wanted Gino can lock this up for years in court. The smart play would just be to stick to solid colors/stripes/half and half colored shells. Anything.