The TAIR source code, version 1 as of August 31, 2013, is open-source software licensed under the Lesser GNU Public License.
Later versions of the software are not yet available for licensing.
You can find the TAIR source code, version 1, at GitHub. There is additional source code for CGI programs at GitHub as well.
Phoenix Bioinformatics Corporation licenses TAIR data and content files with individual corporate and institutional licenses. All other access and use of TAIR is governed by the Terms of Use Agreement published on this web site.
From the Terms of Use, "Upon your agreement to utilize the Service on the terms described herein, you may extract, download, and make copies of limited excerpts of the information contained in the Service as necessary for your academic and non-profit use. You may create works based on the data and freely redistribute those works. You may not otherwise copy, replicate, share, redistribute, or facilitate access to substantial subsets of the Data or Materials or the Service or in any form, for example, the files in the Subscriber_Data_Releases folder, without written permission from Phoenix Bionformatics. Files in the Public_Data_Releases folder are made available to the public under the CC-BY 4.0 license (https://creativecommons.org/licenses/by/4.0/).
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By using the Service, you agree to provide attribution to TAIR. To attribute the use of the Data to TAIR, you must cite at least one TAIR publication in the way specified at http://www.arabidopsis.org/about/citingtair.jsp or in a substantially similar manner. You must also supply the URL of these Terms of Use: http://www.arabidopsis.org/doc/about/tair_terms_of_use/417. "
If you use any of the data or code licensed on this page, you should cite TAIR using the standard citation.