Maybe you think (or read) for once before you post. This is not and never was about a patent. Makes me want to avoid elevators all together. Unsolicited information that on top of it is also wrong.
Boats, I don't see why this would be apples and oranges. Mercedes can put their star on their cars and BMW can put their kidney on their cars. Whether Mercedes also makes trucks that bear the star or not is really of no relevance.
Once again.
Mercedes uses the three pointed star on all of their products--they won't be licensing it out to BMW.
BMW's grill has been aped before. Pontiac has been doing it off and on for decades, but no competitor dares use the propeller.
Spyderco claims the "round" hole as a trademark--it's industry-wide mark of quality.
Why then does it matter that Busse's "Talonhole" is on the choil? It's still a round hole. Spyderco makes no mention that the location of the hole matters, and looking at the Spyderfly, The hole need not appear near the spine of the blade.
Spyderco was founded in 1978. The Worker came out in 1981, the first with the hole.
Jerry Busse has been making salable knives since at least 1982, but the choil hole is not even a remotely uniform trademark throughout the 80s. It began appearing more consistently since the 90s, but one can readily find pictures of older Busses, and not just the "field grades" that one has to read markings on to know it is a Busse. That is simply an evolutionary matter.
Nevertheless, Sal had his round hole well marketed long before Jerry had his.
If the round hole is the trademark, why should it matter whether it appears near the spine or on the choil? If Pontiac puts a BMW propeller on a rear quarter panel, a place it is never seen on a BMW, is that legitimate just because they moved it?
One possible explanation is that Spyderco would find it fruitless to chase off Busse at this late date. In Oregon recently, we had the Tillamook Cheese factory going after jerky maker Tillamook County Smoker for trade dress infringement based on the name Tillamook. The case was thrown out because Tillamook Cheese had allowed the situation to persist in the market for far too long and had not aggressively defended its trademark.
Then again, the Spyderhole obviously started off as a patented opening device and only in 1995 was it trademarked. Maybe Busse beat Spyderco to the trademark office, or Busse limited his to a round hole on the choil.
Nevertheless, it is all very interesting, and obviously the fecal matter has never really hit the fan on these issues or they'd have been sorted out by now.
I can still not think of any company in any field which licenses its trademark to a direct competitor. The point of a trademark is to reduce market confusion, not increase it.