' Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
' documentation files (the "Software"), to deal in the Software without restriction, including without limitation
' the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and
' to permit persons to whom the Software is furnished to do so, subject to the following conditions:
'
' The above copyright notice and this permission notice shall be included in all copies or substantial portions
' of the Software.

In other words: you can even sell DNN itself to your clients (although i think you would have to answer some questions if they'd ever found out that you sold them free software ...), all you have to make sure is that the source includes this license text and the copyright notice.

You can turn off all copyright notices in the HTML generated by DNN, in host>settings. It is not necessary to include a "powered by DNN" icon anywhere (although you are allowed to do that of course ;))

IMO this liberal license is one of the reasons we have such a lively market for commercial AND free modules, services, hosting.. etc.

Cheers,

Erik