According to the terms of the nopCommerce license, you may NOT remove or hide the "Powered by nopCommerce" statement that appears at the bottom of each page within nopCommerce shopping cart.
If you have not purchased a valid "Copyright notice removal license" for nopCommerce, the copyright notice at the footer of your store must remain intact, unedited and clearly visible. Don’t attempt to edit, remove or hide the copyright notice in any way. It does not give you authorization to remove any copyright notices in the script source files nor any other rights. We will contact the hosts of any users violating these terms, requesting your website be taken down immediately under the DMCA act. Copyright infringement is illegal - be advised!
Upon purchase of a "copyright notice removal key" you are permitted to remove the aforementioned proprietary notices. A single key must be used for each store (URL) and may not be used more than once. You may not use a key to remove copyright on unlimited store installs on one website domain.