So to clarify, there is 2 types of patents as stated, and 2 types of trademarks as well. As a manufacture I myself assume zero responsibility in patent infringement, On my stock molds nor on my production molds. A fishing lure can have a design patent, a utility patent, and or both, as well as a design trademark. Coke bottle as exampled above is actually covered under trademark law, as well as mc ds arches and several other things. In the end it is sole responsibility of the end user to verify they are not violating patent laws. The very easiest way to know is when your ripping off other bait parts, there will be a patent number right on the bag. research it at uspto.gov and figure out what it covers. If there is not a number on the bag, and there is indeed a patent. They cant do anything about it, But that don't necessarily mean the person you are taking from did not do there research either. And they to could be violating a patent.