The University of California is fighting back in its quest to regain control over the rights to the powerful gene-editing technology known as CRISPR-Cas9. On Monday, in a case before the United States Court of Appeals for the Federal Circuit in Washington, D.C., UC asserted that the valuable patents on the revolutionary tool belong to UC, not the Broad Institute of Harvard and MIT - and that the nation's patent office committed serious legal errors when it ruled in 2017 against the University of California.