Licensing FAQs

Here you can find answers to frequently asked questions about our licensing

Prior to 22nd January 2024, Seldon licensed MLServer, Core 1, Core 2, Alibi Explain and Alibi Detect under the Apache License Version 2.0 (“Apache 2.0”), with Core+ and Seldon Enterprise Platform licensed under commercial licensing models. 

As of 22nd January 2024: 

  • Core 1, Core 2, Alibi Explain and Alibi Detect are now licensed under the Business Source License 1.1 at no cost for non-production uses (with a limited exception for non-profit education institutions) and under other license terms for production uses; 
  • MLServer will continue to be licensed under the Apache 2.0 license; 
  • Core+ and Enterprise Platform are only licensed under commercial licenses.  

For information about paid licensing arrangements for Seldon’s software, including for production or commercial use, please contact us. 

The BSL is a source-available license that is an alternative to open source software license models. Under the BSL, the licensed source code is made publicly available for non-production use of the licensed code at no cost.  The licensor may also grant Additional Use Grant(s) for production use subject to restrictions imposed by the licensor.  

Software licensed under the BSL is guaranteed to become open source under a specified “Change License” at a “Change Date” in the future.   

For software products licensed under the BSL, Seldon grants licensees the right to copy, modify, create derivative works, redistribute, and make non-production use of such software. All modifications and derivative works of the licensed software are also subject to the BSL.  

Except with respect to the Additional Use Grant offered by Seldon, licensees cannot use the software licensed under the BSL for any production use. In addition, licensees must display this BSL on each original or modified copy of the licensed software.

Seldon’s Change License for Core 1, Core 2, Alibi Explain and Alibi Detect products is the Apache License Version 2.0. 

Seldon’s Change License for Core 1, Core 2, Alibi Explain and Alibi Detect products is four years from each version release.   

Yes. Both the source code and binaries for Core 1, Core 2, Alibi Explain and Alibi Detect are subject to the BSL.

Under Seldon’s BSL, Seldon grants a limited right to non-profit educational institutions to use the licensed software for production use. Such production use cannot include commercializing the licensed software or incorporating or including the licensed software into any models, products or services sold, licensed, marketed, or offered for sale to third-parties. 

Future releases, starting with Core 1.18, Core 2.7, Alibi Detect 0.11.5, Alibi Explain 0.9.5 will be licensed under the BSL.

For releases from 22nd January 2024, you can continue to use Core and Alibi in a development or test environment. If you deploy machine learning models in production with Core, or use Alibi on models in production, you’ll need to purchase a subscription. 

Any model which is not in a pre-production environment, including development, testing, or staging.

Production use of Core and Alibi is available under a commercial license.  Refer to our pricing page for pricing and purchase options.  Under this license, customers may not commercialize Core or Alibi, or include them in any models, products or services sold, licensed, marketed, or offered for sale or licensing to third-parties.  If you wish to use Core or Alibi as part of a product or service, contact [email protected].   

No. Users with a Core license have access to both Core 1 and Core 2 throughout the length of their original license. Users with an Alibi license have access to both Alibi Detect and Alibi Explain throughout the length of their original license.   

Production use of Core and Alibi is not permitted under the BSL, whether on a standalone basis or as part of a product or service. For partners needing to use Core and/or Alibi in their own commercial solution, please contact [email protected]. 

If you’re already a customer or have an agreement to redistribute our software, there is no change.

For commercial applications, to redistribute our default distribution under the BSL, reach out to our team to discuss. We’re happy to help if you have any questions: reach out to us at [email protected] to discuss your particular situation. 

No. The modified version (together with the original Seldon software) constitutes a derivative work of the original Seldon software licensed under the BSL. Under the BSL, modified versions are also subject to the BSL and cannot be redistributed under a different license. 

The merged code will be bound by the BSL (or the Change License after the Change Date) with respect to the Seldon code components and the license(s) applicable to the other code with respect to the non-BSL components. So, merging BSL code and code licensed under a less permissive license may be challenging. If mixing Seldon’s code with code licensed under certain permissive licenses (such as Apache Version 2.0), you may also provide the entire program under the BSL with a notice for the permissive (e.g. Apache 2.0) portion.

Non-profit educational institutions may use Core or Alibi projects for production uses; provided, that such use does not include commercializing the products or incorporating or including the products into any models, products or services sold, licensed, marketed, or offered for sale to third-parties.  

Existing customers and partners using Seldon products under a commercial license are not affected.

Seldon software licensed by a user prior to January 22nd, 2024 remains licensed under the applicable license. For users who licensed versions of MLServer, Core 1, Core 2, Alibi Explain and Alibi Detect prior to January 22nd, 2024, the applicable license is Apache License Version 2.0. You may continue to use the software versions released prior to January 22, 2024 under the original license.

First, a big thank you! You can continue to contribute to Seldon’s open source and source available products as you always have, whether that code is under the ‌Apache 2.0 or BSL licenses. To learn more about how to contribute, see our contributor guide.

We are committed to our open core business model, which means offering products along the licensing and pricing spectraFor Seldon, this means offering our base product, MLServer, under an open-source license, our mid-level products, Core and Alibi, under a source-available license (with commercial license options for production use), and our enterprise grade products, Core+ and Enterprise Platform, under commercial licenses.

We no longer refer to these software distributions as open source. We updated our website and our messaging to refer to these products as “Free & Open,” and when talking about the licenses directly, we describe them as “source-available.”  

Our commitments to the principles of open source have not changed at all over the past decade — we always have and always will value transparency, collaboration, and community.   

MLServer, as the starting point in the ML production journey, will continue to be available under the Apache License Version 2.0. The Apache License Version 2.0 is a permissive free software license. Subject to certain notice, disclosure, attribution and other requirements set forth in the Apache License Version 2.0, licensees enjoy broad rights to use, modify, distribute, or sublicense the code licensed under the Apache License Version 2.0.  We will also continue to contribute to other open source projects, as we have always done. 

For information about Seldon and the licensing models for Seldon’s software, please visit the following resources or contact us at: [email protected] 

  1. License Announcement 
  2. Selon Core License Agreement
  3. Seldon Alibi License Agreement

For media related enquiries, please contact [email protected] 

For questions about licensing and clarifications on usage restrictions, please contact [email protected] 

We’ve put together a comprehensive list of questions and answers for you.

Can’t find the answer you’re looking for? You can ask our team here.

See how Seldon
works for you

Serve, monitor, and manage
your models today.

Seldon Technologies Limited, registered in England and Wales with company number 09188032

Registered Address:
45 Gresham Street, London, EC2V 7BG
United Kingdom

SELDON, SELDON CORE, SELDON DEPLOY, ALIBI and the Drop Logo are all trade marks of Seldon Technologies Limited

Rise London
41 Luke Street

UK: +44 (20) 7193-6752
US. +1 (646) 397-9911

Email: [email protected]