 <p>This behaviour is fixed in the latest <a href="https://github.com/jzaefferer/jquery-validation/archive/master.zip" rel="nofollow">jquery-validate.js on github</a>. The bug was reported as </p> <blockquote> <p>'E-mail validation fires immediately when text is in the field'</p> </blockquote> <p><a href="https://github.com/jzaefferer/jquery-validation/issues/521" rel="nofollow">bug report and discussion here</a> </p>