Patents thickets hinder innovation

A “patent thicket” describes a web of patents filed on a single existing product to create barriers to competition and extend effective patent life. The US Patent and Trademark office (USPTO) grants patents on new and novel inventions, for example the active ingredient of lifesaving drug – this is known as the “parent patent.”

Pharma companies build patent thickets by making small changes to a parent patent and subsequently applying for “off-spring patents.” USPTO may reject some off-spring patent applications because they have been deemed not different enough or not “patentably distinct” from the parent patent.

To circumvent a rejection of a such a patent application, Pharma companies file terminal disclaimers on these off-spring patents applications. Terminally disclaimed patents have the same patent protection period as the parent patent but allows Pharma companies to build a thicket around the parent patent.

Challenging the validity of an off-spring patent is costly and time consuming, because a generic or biosimilar that seeks to challenge the validity of an off-spring patent must invalidate every single patent in a thicket.

For example, AbbVie built a patent thicket of over 130 additional and duplicative off-spring patents on the drug Humira. AbbVie applied for numerous offspring patents, including on the injector device used to deliver the medication, the injector firing button, and a specific dosage of Humira for a condition that it was already known to treat. AbbVie has stated that any generic or biosimilar company seeking to challenge any patents in their thicket would have a total litigation time of 4 to 5 years.1