Evergreening is the strategic extension of the duration of a temporary monopolistic or market dominant position by means of IP strategies, and in practice patent strategies particularly. This paper explores the evergreening phenomenon. After an introductory description of evergreening and its associated innovation and IP policy issues, the paper provides a literature review. We further present one case of the pharmaceutical blockbuster drug Losec (Omeprazol) that became the world’s best selling drug from 1996 to 2000. The case is accompanied by short evergreeing examples based on other IPRs such as trade marks. A theoretical part discusses different types of evergreening approaches along with simple models. The paper ends with a discussion of implications for managerial counterstrategies and innovation and IP policies.