While not entering into the debate (have been down that road too many times now!), I would like to provide a link to
a thread where we have discussed this issue in the past and currently provide a status on the state of the "Original By" which has never functioned properly but is being worked on by Maxis.
Also, there is indeed a bug that we have reported
here that is causing an incorrect "Original By" to get assigned to a lot. The best way to prevent it is to 1) bulldoze the lot you are going to use, 2) save the empty lot to your library (verify that the original by is blank once it's saved), and 3) place empty lot from your library back onto the lot.
Finally, for those that may have missed it in the patch notes, Maxis themselves posted on 6/11/15 that "We fixed a plagiarism issue that was allowing the “Original by” creator information associated with a lot or room to become lost after using the placement option via Manage Worlds and then re-uploading the lot to the Gallery." To me, this indicates pretty clearly that Maxis intends original creators to retain credit for their creations. Many of us believed this prior to their statement; otherwise, why would the "Original By" have even been implemented? But it's good to have it directly clarified.
