People stealing my dupes?

[Nevy]

No, why would you want a rule to stop it? Be proud your ideas used, don't cry at the fact someone likes it and would like to make one like it.

I kind of agree and kind of disagree.

There are some things that take time, effort and creativity.
It is disrespectful to find that someone stole a dupe or is re-selling a dupe you sold to them.

However, if they can manage to rebuild it then that is more respectable unless it is a unique idea.

I myself created the cube casino game and have sold multiple versions of dupes that have exceeded $100k. I always make the cost of a dupe relevant to it's use, the value of it and the probability of it getting leaked or re-created. I have had quite a few people come tell me that they want my dupe for a low cost because, "It isn't that hard to make but I am too lazy to build it." If they have the willingness to re-create it, great. If they want to copy my idea and try to use it to make money, we have a problem. (In most cases)

I have had two people copy my game, one of them being Lesanka. It was funny seeing the same game but there was nothing I could really do (Besides RP a lawsuit for copyright infringement). They did manage to make a nicer casino to have the game in and I respected the amount of effort they put into it and it looked far better than I cared to make mine! 

All I can recommend is that when you sell one of your dupes, you tell them that if they sell it/ give it to another person, they would be blacklisted from purchasing ANY other dupes that you are selling. With people who admire a building/creation of yours, they are likely going to not risk leaking it.