Do you know that Signature Campaign is an invention of bitcointalk.org?
I didn't know before now. I had thought that signature campaign is something that has been in practice even before creating the bitcointalk forum. But I was surprised to discover otherwise. I searched the internet for ways to earn bitcoin. Many blogs including binance news acknowledged that signature campaign is a means to earn bitcoin and it was started or it is exclusive for bitcointalk forum. Even 99bitcoins said a similar thing.

This is nice to know that apart from the Bitcoin - Pizza event, HODL typo error incident, there are other things that emanated from the bitcointalk forum.

So, apart from here in bitcointalk, has any other forum or website adopted the signature campaign system of advertisement?
Does theymos have a patent for signature campaign such that no other forum can replicate what is happening here without his permission.