Is there a way to punish such plagiarism? must take measures to prevent this incident.
There is, and already applied here. Permanent ban.
I don't think that it would be applied here since he copied from other forum and pasted on other forum. I think bitcoingarden staff already carried out an action since I don't find the thread that was plagiarized there.
And I also often encounter cases others took my bitcointalk account to participate in other bounty programs.
There is no other way to do this except you have to report that case to the BM. Unless BM changes the way how to participate in a campaign, such as providing proof of authentication, then there is no way to prevent someone use your account and steal your work while providing their own address.
I think proof of authentication by posting tweets, shares link is good way to verify but it is something that spams the thread a lot which is not good IMO. Plus it is of no use if there are careless managers who choose rather to count everyone in and skip some hard work over checking and verifying work and eliminating cheaters.
