Open source software can be sold and used commercially. The financial return on open source software can also come from selling services, such as training and support, rather than the software itself. The use of dual-licensing provides an offer of the software under an open source license but also under separate proprietary license terms. Customers can be attracted to a no-cost and open source edition, then be part of an up-sell to a commercial enterprise edition.Further, customers will learn of open source software in a company's portfolio and offerings but generate business in other proprietary products and solutions, including commercial technical support contracts and services. Another possibility is offering open source software in source code form only, while providing executable binaries to paying customers only. With permissive software, any company can distribute the package without the source or software freedoms.Some companies provide the latest version available only to paying customers. Companies provide proprietary extensions, modules, plugins or add-ons to an open source package. Independent developers often accept donations.

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