Patent-based indicators provide a measure of the output of a country’s R&D, i.e. its inventions. The methodology used for counting patents can however influence the results, as simple counts of patents filed at a national patent office are affected by various kinds of limitations (such as weak international comparability) and highly heterogeneous patent values. To overcome these limits, the OECD has developed triadic patent families, which are designed to capture all important inventions and to be internationally comparable.


A patent family is defined as a set of patents registered in various countries (i.e. patent offices) to protect the same invention. Triadic patent families are a set of patents filed at three of these major patent offices: the European Patent Office, the Japan Patent Office and the United States Patent and Trademark Office.

Triadic patent family counts are attributed to the country of residence of the inventor and to the date when the patent was first registered.

Triadic patent families are expressed as numbers and per million inhabitants.


The concept of triadic patent families has been developed in order to improve the international comparability and quality of patent-based indicators. Indeed, only patents registered in the same set of countries are included in the family: home advantage and influence of geographical location are therefore eliminated. Furthermore, patents included in the triadic family are typically of higher economic value: patentees only take on the additional costs and delays of extending the protection of their invention to other countries if they deem it worthwhile.


Although the volume of triadic patent families remained relatively steady over time, with more than 50 500 triadic patent families filed in 2013, there has been a significant shift in the origin of patented inventions. The share of triadic patent families originating from Europe (26.2%), Japan (26.6%) and the United States (27.0%) report a loss of 1 to 4 percentage points compared to the levels observed in 2003. Asian countries are increasingly contributing to patent families: the most spectacular growth among OECD countries has been observed by Korea, whose share of all triadic patent families increased from 3.8% in 2003 to 5.8% in 2013. Strong rises are also observed for China and India, with an average growth in the number of triadic patents of more than 17% and 12% a year respectively seen between 2003 and 2013.

When triadic patent families are expressed relative to the total population, Switzerland, Japan, Germany, Sweden and Denmark were the five most inventive countries in 2013, with the highest values recorded in Switzerland (148) and Japan (125). Ratios for Austria, Belgium, Finland, Israel, Korea, the Netherlands and the United States are also above the OECD average (40).


Further information

Analytical publications

Methodological publications


Table. Triadic patent families

Triadic patent families
Number per million inhabitants, 2013