The U.S. Patent & Trademark Office (PTO) has handed hedge fund manager J. Kyle Bass’s Coalition for Affordable Drugs its first loss by upholding the validity of the patent covering Shire’s colitis drug Lialda. Bass argued that the patent never should have been issued because it was based on science already in the public domain, but PTO’s appeals board rejected that position. The decision potentially protects Lialda from generics competition until 2020. The coalition has filed more than 30 petitions that seek to nullify what it sees as invalid drug patents. Later this month, the appeals board is expected to make decisions on a patent covering another Shire drug, Gattex, which treats short-bowel syndrome, and on Celgene’s blood cancer drug Revlimid. “We look forward to continuing our work of challenging dubious patents that enshrine monopolies protecting drugs that lack innovation to the detriment of Americans suffering from illness,” Bass says. The pharma sector has charged that Bass is abusing the patent review system as part of a short-selling strategy aimed at driving down the price of drug company stocks.