Surendra/Adobe StockAround 400 U.S. patents contain at least one citation to a retracted scientific paper, a new study has found. Of the more than 13 million patents in the USPTO database, 136,162 contained citations to at least one scientific paper. Of these, 401 patents cited retracted papers: 195 cited the retracted paper before it was filed, 92 cited papers retracted while being examined, and 114 cited a paper that was retracted after the patent was granted, the study revealed. Kim said citing a retracted paper shouldn’t automatically invalidate a patent but argued patent offices and information platforms must be able to identify retracted papers easily. Patents should recognize when papers supporting them have been pulled, she said, because one purpose of issuing patents is to disseminate scientific information.