Until today it is still the case that most scientific publications are never cited

Overall about 50% of the published literature is never cited!!

Next to this, some publications are highly cited, quite often by self-citations.

The record holder in citations is a publication from 1951 about protein measurement. This article has about 200000 citations.

(Lowry O H, Rasebrorrgb N J, Farr A L & Ranrtrdl R J. Protein measurement with the Folin phenol reagent. ,J. Biol Chem. 193:265-75, 1951. (1/77), this article is available on the internet)


As I’m not familiar with this topic I do not know whether or not this is an important invention?


Also in patents we have some families that are highly cited.

Not surprisingly there is a difference in the technology sectors. There is a high citation count in “Chemistry”, but a lower citation count in ‘general’ science (smoking/building etc.)


You would expect that the most cited records are key inventions!

This seems to be true, when we look into the different IPC classes and search for the most cited patent families.

Unfortunately there are not many tools available to give us the possibility to rank on citation count. (I’m aware of Patbase from Minesoft to offer this option.)

For sure some key inventions can be identified this way.

I will give three examples:

1)      The basic patent on PCR technique used in biochemistry is EP0201184  from Hoffmann La Roche ( >5700 citations)

2)      Integration of GPS in PDA’s based on US5559707  (and WO9748065  ) by David Delorme, who was frustrated about the low quality of maps available in the US (>3300 citations)

3)      Bubble jet printing technique as protected by Canon

The patent family, with DE2843064  as the first publication, is cited almost 3000 times

These seem to be indeed key inventions.

This trick can be used for Patent Landscaping as well.

From the key inventions it is very easy to extract all forward citations and look to the relevancy for your Landscape.

Some warning is necessary as we know the difference in citation policy between EPO and USPTO. Next to this we also have to be careful as family citations are based on INPADOC families. These families are sometimes covering many different inventions, due to the complex structure of INPADOC families (All the documents directly or indirectly linked via a priority document belong to one patent family.).


Good luck in using this option!!

Aalt van de Kuilen

Senior Patent Information Specialist in the field of Life Sciences and Chemistry. Read more about the background and expertise of Aalt van de Kuilen.