title: jQuery, jQuery UI, and Dual Licensed Plugins (Dual Licensing)
body: <p>OK I have read many posts regarding Dual Licensing using MIT and GPL licenses.  But Im curious still, as the wording seems to be inclusive.  Many of the Dual Licenses state that the software is licensed using "MIT AND GPL".  The "AND" is what confuses me.  </p>
  
  <p>It seems to me that the word "AND" in the terms, means you will be licensing the product using both licenses.   Most of the posts, here on stackoverflow, state that you can license the software using one "OR" the other.  </p>
  
  <p><a href="http://jquery.org/license" rel="noreferrer">JQuery</a> specifically states "OR", whereas <a href="http://jqueryui.com/about" rel="noreferrer">JQuery UI</a> specifically States "AND".
  Another Instance of the "AND" would be <a href="http://www.trirand.com/blog/?page_id=78" rel="noreferrer">JQGrid</a>.</p>
  
  <p>Im not a lawyer but, it seems to me that a legal interpretation of this would state that use of the software would mean that your using the software under both licenses.  Has anyone who has contacted a lawyer gotten clarification or a definitive answer as to what is true?  Can you use Dual licensed software products that state "AND" in the terms of agreement under either license?</p>
  
  <p><strong>EDITED:</strong>
      Guys here is specifically what Im talking about on jquery.org/license you see the following stated:</p>
  
  <blockquote>
    <p>You may use any jQuery project under
    the terms of either the MIT License or
    the GNU General Public License (GPL)
    Version 2</p>
  </blockquote>
  
  <p>but in the header of Jquery's and Jquery UI library you see this:</p>
  
  <pre><code> * Dual licensed under the MIT and GPL licenses.
   * http://docs.jquery.com/License
  </code></pre>
  
  <p>The site says </p>
  
  <blockquote>
    <p>MIT or GPL</p>
  </blockquote>
  
  <p>but the license statement in the software says</p>
  
  <blockquote>
    <p>MIT and GPL.</p>
  </blockquote>
  
  <p><strong>UPDATE May 7, 2010</strong>
  There is clearly something to this question as JQuery has changed the wording of thier licence agreement in thier latest release to state MIT <strong>OR</strong> GPL. </p>
  
  <p>Release 1.3.2 license says:</p>
  
  <pre><code>/*
   * jQuery JavaScript Library v1.3.2
   * http://jquery.com/
   *
   * Copyright (c) 2009 John Resig
   * Dual licensed under the MIT and GPL licenses.
   * http://docs.jquery.com/License
   *
   * Date: 2009-02-19 17:34:21 -0500 (Thu, 19 Feb 2009)
   * Revision: 6246
   */
  </code></pre>
  
  <p>But now Release 1.4.2 license says:</p>
  
  <pre><code>/*!
   * jQuery JavaScript Library v1.4.2
   * http://jquery.com/
   *
   * Copyright 2010, John Resig
   * Dual licensed under the MIT or GPL Version 2 licenses.
   * http://jquery.org/license
  */
  </code></pre>