This patent / copyright issue is really causing a lot of undo consternation. The problem is that the laws are very involved; although fortunately, most companies apply a little common sense in enforcing them.
The main point to keep in mind is that most companies will only get nuts about enforcing their patents if it is causing them to lose money. As a general concept, if you reproduce something a company is currently making money selling, they will come after you.
Let's try it this way. I recently lost a hub cap from my IM and decided to replace the other three as well. I wanted Porsche crests on the hub caps. I could buy the hub caps from a lot of sources (because they are generic), but not with Porsche crests. I could have bought hubcaps from Porsche, with the crests. They would not care what I do with them, so long as I buy them from Porsche. The problem is that Porsche hubs don't fit my wheels. And, Porsche doesn't make hubs for cars that are not Porsche.
That doesn't mean it is not legal to have Porsche hubs on a non-Porsche car -- only that Porsche has chosen not to make them. So, I buy generic hubs. Now, (this is where the situation is so often confused) I still don't have the crests. Porsche would gladly sell me crests, but they are $77 a piece from Porsche. Bootleg crests are about $18 a piece.
Problem is, Porsche owns the logo; so any crest but theirs is not legal. If I buy the Porsche crests, they couldn't care less if I stick them on a DeSoto. They haven't lost a dime because Porsche doesn't make a DeSoto. They sold their crests, and I didn't buy bootleg crests. If I buy the bootleg crests, Porsche is losing money on the sale. Someone else is using the Porsche logo, to make money; and in the process, Porsche loses money. That is the key to all this.
How does that translate to the car? It gets fuzzy because we are putting Porsche logos on (not DeSotos, but) cars that look like cars Porsche used to make. Porsche probably still has the rights to the car shape, but they aren't losing money when someone else uses it because Porsche no longer does use the shape to make cars. If it were economically feasible for Porsche to go into the Speedster business again, they would probably run all the other builders out of business (or at least try to). I'm not so sure they could do it because the exact scope of a given patent is not as broad as you might think.
Anyway, Porsche doesn't sell a Speedster shaped car, so why would they want to invest hundreds of thousands of dollars in stopping others from (basically) keeping a Porsche legend alive? That's a rhetorical question, because they probably could start a lawsuit, but it is not guaranteed they would win it; and what would they gain if they did. And what money are they losing right now because others are using the shape? (another rhetorical question).
The only person who has a reason to gripe about a repro with a Porsche badge is an owner of a real Speedster. He's probably not seeing the full potential of his investment because there are so many copy cats around. That may not even be so either, but it is at least theoretically possible. It's not even theoretically possible for Porsche to be losing money on the sale of a repro -- unless it is a repro of a car they still make. Which is why Ferrari takes the position it takes.
Guys, if you want to spend time worrying about going to the big house because you have a car that says "Porsche" that's really not a Porsche -- maybe you will have a cell mate who got put away for tearing the tag off his mattress. Those guys will get in trouble first. Just don't sell your copy cat to some niave Porsche collector and tell him it is a real Porsche. That's a whole different ball game. Sorry for the length of this reply, but if you ask a lawyer what time it is he won't stop talking until he has explained how you make a watch.