The illegal part about them is usually the fraud aspect. You tell your investors one thing but then do something else. One may argue that that's part of the de

The illegal part about them is usually the fraud aspect. You tell your investors one thing but then do something else. One may argue that that's part of the definition of a ponzi scheme, i.e., if you are open about it then it's not technically a ponzi scheme sincs it's lacking that particular necessary characteristic. (With that definition, ponzifarm is not a ponzi scheme.)