Tigra Tree Javascript license description:
There is no license fee or royalty fee to be paid at any time for using the Tigra Tree Menu v1.x
You may include the source code or modified source code within your own projects for either personal or commercial use but excluding the restrictions outlined below. The following restrictions apply to all parts of the component, including all source code, samples and documentation.

    * Header block of script file (tree.js) CAN NOT be modified or removed.
    * The above items CAN NOT be sold as are, either individually or together.
    * The above items CAN NOT be modified and then sold as a library component, either individually or together. 


For more detail, http://www.softcomplex.com/products/tigra_tree_menu/docs/