In an IP infringement case involving the manufacturers of competing children's suitcases the UK's Supreme Court ruled in favor of the makers of the quasi-knockoff.
From BBC:
Supreme Court Justice Lord Neuberger said Trunki was "both original and clever" and he said it "appears clear" the Kiddee Case had been conceived "as a result of seeing a Trunki and discovering that a discount model was not available".
But he said: "Unfortunately for Magmatic, however, this appeal is not concerned with an idea or an invention, but with a design."
Over at the design website Core77, the commenters agree with the court's decision. "Similar, but not the same…. same complaint could be made between automakers… Ford truck looks like Chevy, vise versa….," says Noodle Time. "I think the scary part to designers is the fact that if you conceive anything even remotely related to some other product, you run the risk of being sued, and even if you win, may still be left with a monetary loss."