By Chris Rourk ( February 11, 2019, 2:02 PM EST) -- In the "2019 Revised Patent Subject Matter Eligibility Guidance,"[1] the United States Patent and Trademark Office provides new guidance to patent examiners to assist with the review of claims for patentable subject matter. This guidance is the latest in a line of guidance that responds to the U.S. Supreme Court decision in Alice Corp. v. CLS Bank International,[2] which held that abstract ideas are unpatentable, and which further provided no clear test for determining what constitutes an abstract idea. As a result, district court and Federal Circuit opinions on subject matter eligibility have tried to apply the Alice decision, and have generally made subject matter eligibility determinations on a case-by-case basis....