If you have created a great design then you could patent it couldn't you??
The knife designer doesn't have to patent his designs. He already has a copyright on the design. Legally, he has that copyright from the moment he expresses the design (i.e. make a drawing or a model or something.) He can patent a mechanism, a lock mechanism, for example. But "look and feel" aspects of a design are generally protected by copyrights and they are protected, legally, by copyright from the moment of their expression.
Notice, please, that American knife manufacturers do not do knock-offs. Why? Because they know that they would be sued if they did. The manufacturers who make knock-off knives, and watches and everything else, are just about always off-shore.
But, begin off-shore isn't enough. You don't see European knife companies doing knock-offs either. The companies that do knock-offs of knives and just about anything else are just about always in one of several countries that don't respect internationally-respected copyright and patent laws.
For an American knife designer to sue a manufacturer in China, for example, and recover damages is theoretically possible. But, in practice, it's basically impossible.
American designer and manufacturers can stop imported knock-offs of their designs. That is true. Those folks who import knock-off of anything, from blue jeans to knives often see shipments confiscated by Customs because of copyright, trademark, and patent infringment. So, these importers build the cost of Customs confiscation into the cost of doing business. They just jack up the price of the products that do slip through (or, more likely, just reduce the manufacturing cost which is directly related to quality) to leave margin for those that are lost. It's much like retail stores charging a bit more for every item they sell to make up for what they loose to shoplifters. US Customs destroys billions of dollars worth of knock-off goods every year.
American designers can sue the retailers who sell the knock-off products. And if the product was imported, US Customs can come knocking on your door and confiscate it right off of your shelves any day they want to.
Why can they do that? Because the knives are illegal, that's why. The fact that they didn't stop them when the shipment came in, the fact that they didn't knock on your door yesterday, doesn't make the knives legal or beyond confiscation today.
Yes, designers can sue retailers. But, let's face it: there are so many little retailers out there who are basically worth nothing. It's impossible for a designer to hunt down every one of them and sue each of them.
The fact that enforcing their copyright against the manufacturers and the retailers of knock-offs is impractical does not mean that designers do not have copyrights, legally and morally. And it does not free the rest of us from our obligations, legally and morally, to respect those rights.
I, for example, very much admire Tim Herman's Sliver. I'd love to own one. But, I can't afford it. So, I am deprived. When Delta-Z announced they'd licensed the design from Herman and would be, with his full permission and cooperation, making a production version, a knock-off, of it, I was number eleven in line. Unfortuantely, it didn't work out and Delta-Z had to cancel the project. I'm very disappointed.
I still want a Sliver and I still can't afford one. I'm still deprived. But, if you or anyone else was to offer an unauthorized knock-off, I would never buy one and much as I might want to. Why? Because I respect Tim Herman's copyrights. So, I won't buy one even if I could.
Not doing what you want to do and what you could do simply because you know that even though it's possible and practical it is wrong: that's called responsibility.
If you're one of those retailers selling these knock-off knives, you are -- even if you haven't been sued or arrested for it yet -- you are selling stolen goods. It is illegal. It is morally wrong. And it is sinful.