Trademarks are really a lot different. Because to violate it, you have to sort of impersonate that company. If someone posted, “Craftsman hose adaptor” on ebay, without making it clear that it was not an OEM part, then I think they could get in trouble with trademarks. Especially if it had a logo on it, or the packaging, or linked to craftsman.
I have heard that rule before about defending trademarks, but I thought that was limited to Europe or something. I am also not an expert.
In a high school business class of mine, Scotch Tape and Kleeenex were held up as examples of how a trademark can be lost if the brand name becomes common usage for a type of product, and the trademark holder fails to defend the trademark. I noticed the circled R when I searched for Scotch Tape, so maybe they managed to claw back their trademark…though I noticed that it seems to be called “Scotch Brand Tape” now. And it was my fuzzy memory of that class material that had me wondering if Legos prime objection was that something that wasn’t a true Lego having been labeled as Lego rather than the copyright infringement.
This came into play with the factory five cobra replica. They were allowed to spend YEARS building them with no fuss, and part of the defense (of course nowhere near close to all of it) in the lawsuit included a survey asking people what they thought of when they saw a cobra (or something like that). About 3/4 associated it with factory five. They ended up settling, and got a document guaranteeing they wouldn’t be harassed about the cobra or the type 65 kits. Now, there really is only factory five making unlicensed replica kits. The other companies pay a hefty licensing fee.
Dave Smith (owner of factory five) told the story on a Facebook live video at the beginning of covid lockdowns. Interesting stuff.
As far as I know Lego does not have a copyright or patent on the blocks itself because they were too stupid to get one (or sth. like that). That’s why there are so many legal knock-off brands.
Lego had a bunch of domestic patents around the world (first one in 1958). The last of the basic ones expired in 1989. Only the name is protected.
That’s why they started joining forces with all the entertainment franchises for the branded kits.
Seems to have worked well for them.