Business models for open-source software

Open-source software is widely used both as independent applications and as components in non-open-source applications. Many independent software vendors (ISVs), value-added resellers (VARs), and hardware vendors (OEMs or ODMs) use open-source frameworks, modules, and libraries inside their proprietary, for-profit products and services. From a customer's perspective, the ability to use open technology under standard commercial terms and support is valuable. They are willing to pay for the legal protection (e.g., indemnification from copyright or patent infringement), "commercial-grade QA", and professional support/training/consulting that are typical of commercial software, while also receiving the benefits of fine-grained control and lack of lock-in that comes with open-source.

Much unlike proprietary off-the-shelf software that come with restrictive licenses, open-source software is distributed freely, through the web and in physical media. Because creators cannot require each user to pay a license fee to fund development this way, a number of alternative development funding models have emerged.

An example of those funding models is when bespoke software is developed as a consulting project for one or more customers who request it. These customers pay developers to have this software developed according to their own needs and they could also closely direct the developers' work. If both parties agree, the resulting software could then be publicly released with an open-source license in order to allow subsequent adoption by other parties. That agreement could reduce the costs paid by the clients while the original developers (or independent consultants) can then charge for training, installation, technical support, or further customization if and when more interested customers would choose to use it after the initial release.

There also exist stipends to support the development of open source software, such as Google's Summer of Code.

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