All of Sputnik's code is open source / free software.
Most of the code is distributed under permissive MIT/X license. There are no GPL-like "copyleft" restrictions on Sputnik's code, but the license is compatible with GPL. (You can incorporate Sputnik's code into GPL code). The spirit of the license is that you are free to use Sputnik for any purpose at no cost without having to ask us. If you want to distribute a substantial part of Sputnik (by itself or as a part of your product) you should give us credit by including the appropriate copyright notice somewhere in your product or its documentation.
Some 3rd party elements (e.g., icons) are available under other open source licenses, such as LGPL, BSD, SIL Open Font.
Please see the source code for details.