I see these guys are still up to their tricks of claiming DNN as their own and selling it for between $500-$5000.  Seems less than a moral business and I'd uspect breaks some of the usage rules by claiming you created it yourtself.

[website name removed]

- Our software is built using proprietary ASP.Net, SQL Server, MS Access and follows Microsoft's best practices.
- Login has a login lockout if too many tries are made to guess userid/password.
- Security system based on "member roles" and with this you can set tune access not only to page, but to modules on the page.
- This software is on it's 4th major release.
- Our developers are developing modules for CRM, Business Orders, Accounts, Contacts, Quotes, Inventory and Storefront.

Yes it is probably legal although questionable in ethical terms.  Just sad to see people that claim other's work as their own, even thrid party skins.  A search on the company name reveals some interesting info, such as them spammign newsgroups frequently and also being caught spamming Wikipedia and using fake accounts to post replies to their own story.  They also seem to be accused of republishing articles without permission.

[link removed]

I guess in the end one can do what they like, but it all comes down to having some morals and business.  Would your clients want you working in such a way?