The best way to prevent accepting bad data from a third-party service provider is to implement business rules to reject invalid data. Business rules are logical statements that define the data quality requirements and standards for the organization. By implementing business rules, the organization can ensure that only data that meets the predefined criteria is accepted into the enterprise data warehouse. Obtaining error codes indicating failed data feeds, purchasing data cleansing tools from a reputable vendor, and appointing data quality champions across the organization are useful measures to improve data quality, but they do not prevent accepting bad data in the first place. References: ISACA Journal Article: Data Quality Management