A potential Taverna user emailed support@mygrid and asked what were the licensing details for using Taverna.
Stian Soiland-Reyes replied (2010-07-28):
Note that this is a reply from a software developer, not a lawyer, so I can't guarantee that this is legally correct.
Taverna is free to download and use for anyone, including commercial companies. You can use Taverna as you please, and there are no restrictions on the workflows and data you might produce using Taverna. We will not collect any dat or workflows (except for any voluntarily submitted user registration data), and you are free to distribute what you produce using Taverna under your own conditions. You can compare this to how you are free to distribute any Word documents you produce using Microsoft Word, which software itself can only be distributed according to your license agreement with Microsoft.
As for deployment you can deploy as many instances as you like of the server and the desktop for commercial use without any charges. As with most commercial and open source software there is no warranty implied.
If you decide to reuse public workflows from myExperiment, they will be indicated with which licence they are distributed under. The most typical workflow licence is the "Creative Commons Attribution-Share Alike 3.0 Unported License", which would allow you to reuse the workflow as long as you give attribution to the original author, and distribute the new workflow under the same license. However, if you only share such a workflow within the same legal entity (your commercial company), I believe it would not constitute 'distribution', and you should not be affected. Any workflows you write from scratch would not be limited by any such licenses, and you can distribute or not distribute these as you please.
Taverna workflows are built by connecting local and remote services. If you use only locally supplied services such as command line tools, you are free to invoke these according to your own regulations.
If you use public third-party web services from your workflows you might face usage restrictions by the individual service providers, for instance on maximum number of queries per day. Many of these services provide mechanisms for setting up your own company-wide mirror of the service, for instance Ensembl allow you to FTP down mySQL dumps of their databases.
As a private company you would likely be using your own set of services to avoid disclosing details such as which compounds you are investigating in queries to public databases. In this case you would only be limited by the individual mirroring clauses of the services you choose to set up. If you develop your own in-house set of services and tools you should not face any such legal limitations.
It is possible to customize the Taverna installation as to which services would be presented as available to the workflow designer, so you can include your own services, and exclude the default public
service listing. If you want to specifically prevent users from calling public web services (which they could manually add to Taverna) you are advised to maintain a firewall blocking/logging such requests.
Taverna will generally show the hostname of the services used in a workflow, so it should be possible to identify if a service is public or company-provided.
You can also disable some of Taverna's plugins which could be used to access public services.
Distribution and modification
The Taverna Software itself is distributed under the LGPL 2.1 license 3. You are free to distribute and run this software as you please if you don't need to modify it. If you provide the Taverna software to other organisations, they would be entitled to ask for the Taverna source code, which is available from our download site.
If your software developers want to modify our software, and your modifications are only connecting to existing APIs in Taverna, you would be free to do so according to the LGPL license. Such extensions can be distributed by you according to your own terms. Taverna provides various plugin points for modifying the user interface, execution and storage, in addition to a plugin installation and update mechanism which you can utilise for this purpose. We recommend your developers to contact the 'taverna-hackers' mailing list for details.
If you want to modify core functionality of Taverna (any piece of Taverna's source code), you are also free to do so, but only as long as you also distribute the source code for those modifications under the open source LGPL license. Again the rule about legal entities applies, so sending the software to other employees would not constitute distribution, but giving it to a different company would. Note that this would still allow you to at the same time distribute extensions according to the API which would not be covered by LGPL, unless you made changes to the core functionality which would only work if combined with your closed-source product. (You can still do that by linking to your closed-source product by creating a new Taverna API which would allow other users to provide an alternative product.)
If you integrate Taverna with your product you would not typically need to modify core functionality of Taverna. We have seen several users extend Taverna using the official APIs, and also integrating
execution of Taverna workflows into web sites and desktop software. We provide a command line tool and a REST/SOAP-based Taverna Server which should be easy to use for
integrating workflow execution into your company's software suite. These tools are distributed under the same terms as the Taverna workbench, and you are free to interface these using any kind of client software.