Berkeley researchers lost big in a Patent Trial and Appeal Board fight over a gene-splicing patent worth billions of dollars. PTAB found a Broad Institute at the Massachusetts Institute of Technology patent for a technique called CRISPR-Cas9 in multicellular organisms didn't violate Berkeley's patent for single-celled organisms. The technique is sparking a gold rush in medical research in fighting diseases and reversing genetic mutations. The decision has been appealed to the U.S. Court of Appeals for the Federal Circuit, and marked the last big interference case under old patent rules.