Portableapps dot com has been going since 2004 and is a legitimate company, they DO NOT "knockoff" software and have been recommended by CNET, PC World, Wired, Lifehacker and more. They are fully transparent about what their company does and licensing.
To quote them, the download they provide "assists with running CCleaner® portably" and:
Online Installer: The ccPortable installer will download the base app from the publisher's server during installation. CCleaner® is a registered trademark of Piriform Ltd. PortableApps.com is not affiliated, sponsored, authorized or otherwise associ