Home Law GAO Unconvinced by Challenge to Sole-Source BPA; Castro & Company, LLC, GAO... LawNewsProtestsResource Library GAO Unconvinced by Challenge to Sole-Source BPA; Castro & Company, LLC, GAO B-419366 February 25, 2021 68 Share FacebookLinkedinTwitter liveostockimages | Shutterstock You must be a Paid or Free Trial Member to Access this Content. Paid members, please login to view your news subscription(s). RELATED ARTICLESMORE FROM AUTHOR Expert Opinion GAO Decision Shows Danger of Allowing SAM Registration to Lapse During Solicitation Period Cyber GAO: NASA Needs a Plan to Update Their Cybersecurity Standards Law Protested Wanted More Time to Prepare Bid for Pressure Washing Services. GAO Wasn’t Sympathetic.