Some activists allege that companies file additional patents on existing products to “extend” the life of the product’s original patents, a practice that’s often dubbed “patent evergreening.”
But patenting a genuine improvement of an existing product has zero effect on the life of the original patent, nor does it deter generic competition. Patenting a new formulation of a medicine would not delay the expiration of the patent on the original version of the drug.
So-called “secondary” or “follow-on” patents, sometimes filed years after the initial patents for a product, definitionally represent additional, real innovations. After all, the USPTO only grants patents to inventions that are novel, useful, and non-obvious.
Contrary to what some groups claim, secondary patents are not “small” or “trivial” improvements. Updated medicines offer real benefits for patients. For instance, an updated drug might include a time-release function that reduces the chance of an adverse reaction. Or new tablets could allow patients greater dosing flexibility. New versions still require years of expensive, risky research to win regulatory approval.