Risk identification is the basis of risk management. Studying identification method of IP risk (factors) in outbound purchasing patents is necessary for good practice in the IP risk management, which must be of great significance for successful patents acquisition. Based on the practice in IP risk management, this article discusses the identification rationale and principle, submits a set of systematic identification methods, including business objectives, system methods, identification tools and evidence-based practice, in order to prevent a major omission in IP risk (factors) identification of the patents of the target company, and safeguard outbound patents investment safety.