I'm not anti-IP per se, but I do wish that Benchmade didn't make the only legal knives with an axis lock. But maybe that makes me anti-IP.
Also, the difference is that spyderco's trademark is a true trademark- meaning a distinguishing mark that can identify the model, but doesn't restrict functional usage of the same idea in a barely different shape. Look at the original Benchmade AFCK, to get both companies involved. Initially, they used a spyderco round hole with a non-patented linerlock. Now, they use an oval hole with their proprietary axis lock. Adding a few degrees difference to change a circle to an oval isn't a functional difference, but an aesthetic one.
An axis lock, or hook that catches pockets, are functional designs that do restrict functional equivalents according to the patent and trademark protections they have been given. Maybe it will be narrowed, but as is, they prohibit functional equivalents.
Zero