Evergreening of patents refers to the practice where patent holders, especially pharmaceutical companies, try to extend the life of their patents beyond the standard 20 years. They do this through legal and technical strategies that delay generic versions from entering the market.
This practice does not involve extending the original patent itself. Instead, companies file for new patents on minor changes or improvements to the existing product. These can include:
- Slight changes in formulation
- New delivery methods (e.g., tablet to capsule)
- Using a different salt or crystal form
- Combining the drug with another compound
- Patenting a new use of the same product
Though these changes may seem minimal, they allow companies to keep exclusive rights and block competitors from producing affordable generic versions. This means higher prices for consumers and a delay in access to life-saving medicines, especially in developing countries.
Why Do Companies Evergreen Patents?
The main reason is profit. Developing a new drug is expensive and risky. So once a company finds a successful product, it wants to keep earning from it as long as possible. Evergreening ensures continued market control and steady revenue flow.
Legal and Ethical Concerns
Many legal systems now recognize the negative impact of evergreening. For example, India’s Patent Act (Section 3(d)) prevents patents on new forms of known substances unless they show significant improvement in efficacy. This rule helped India reject a patent for a cancer drug by Novartis in the famous Glivec case, allowing affordable generics to reach patients.
Critics argue that evergreening hampers innovation. Instead of investing in genuine research, companies focus on tweaking existing drugs to prolong exclusivity.
