This case study outlines the implementation of 340B Vigilance by a leading pharmaceutical manufacturer to address challenges related to the 340B Drug Pricing Program. The manufacturer faced significant issues, including a lack of visibility into prescriptions dispensed from 340B inventory, extensive manual efforts to identify ineligible or duplicate rebate claims, and revenue loss due to duplicate discounting. To mitigate these problems, the manufacturer sought a solution that would provide visibility into prescriptions dispensed by covered entities and their contract pharmacies. They implemented Validata, a script validation tool that integrates with a third-party portal to manage prescription-level data. The addition of the 340B Vigilance module has enabled the manufacturer to prevent over $50 million in rebate overpayments in the first year and improve accuracy in managed care and rebate processing. Future plans include integrating ineligible service provider data to further enhance the validation process.