On March 4, 2014, the US Patent and Trademark Office published new examination guidelines for determining patent eligibility under 35 U.S.C. 101. The document, entitled "Guidance For Determining Subject Matter Eligibility Of Claims Reciting Or Involving Laws of Nature, Natural Phenomena, & Natural Products,” implements a new procedure to address changes in patent eligibility law after the Supreme Court decisions in Association for Molecular Pathology v. Myriad Genetics, Inc. and Mayo Collaborative Services v. Prometheus Laboratories, Inc.
The document primarily addresses patent examination in biotech applications. The document does not change the examination of claims reciting an abstract idea, which is more prevalent in the software and computer arts. The guidelines can be found here [link]
and the quick reference sheet here [link].