AlaCarte Patents

A division of Business Metamorphosis LLC

Jump Within Page to:
Competitive Analysis
Technology Transfer

Who has been reading your patent?

Lessons from Patent Citation Analysis

Version of 25 August 2007

I. In Citations

When a patent is examined the patents cited in the examination are listed in the document. Thus if your invention is patented, later inventors who work in the same area and make improvements on your invention or use it to create new inventions may "cite" the invention in their applications, or the patent office may make the citation by identifying your patent as relevant to the subsequent one.

Generally speaking the more often a patent is cited the more significant it is. It is often quite useful to the owner of the cited patent to know who has been reading their patents and what they have been doing with the information, as that may indicate the directions that competitors or the industry are going.

There are any number of things you can learn from a citation analysis but often the most interesting are the inventor and the assignee (company) of the citing patent.

A. Citation Analysis Examples

Table I shows the citations of a given patent. This table which is easily obtained, is just the first step in a citation analysis This table shows the patents who cited 6,394,963 when examined.

Table I—Citations of US Patent 6,394,963

Index	Number	Title
1	6,896,655	System and method for conditioning the psychological state of a subject using an adaptive auto stereoscopic display
2	6,805,074	System and method of customizing an animal feed based on heat increment
3	6,746,409	Technique for diagnosing attention deficit hyperactivity disorder using complimentary tests
4	6,652,470	Using image modification and temperature biofeedback to diagnose and treat ADHD
5	6,589,171	Sensor glove for physiological parameter measurement
6	6,527,730	Reducing noise in a technique for diagnosing attention deficit hyperactivity disorder

B. Competitive Analysis

Table II gives a more complete picture of what is happening. Note that the patent was cited six times but 4 of those 6 was by the same company. This is usually true when a family of patents is issued that the later ones cite the earlier ones. There are however, two external citations. One by McLean hospital (which bought the patented technology from Kodak) and a totally unexpected one by Cargil in a field completely unrelated to the topic of the invention.

Table II—Citation Analysis of Assignees and Inventors

Patent Number	Title	Assignee	Inventors	Internal or External
6,805,074	System and method of customizing an animal feed based on heat increment	Cargil	Newcome et al	External
	Cargil Count	1
6,746,409	Technique for diagnosing attention deficit hyperactivity disorder using complimentary tests	McLean Hospital	Kiersbilck et al	External
	McLean Hospital Count	1
6,527,730	Reducing noise in a technique for diagnosing attention deficit hyperactivity disorder	Eastman Kodak	Blazey et al	Internal
6,589,171	Sensor glove for physiological parameter measurement	Eastman Kodak	Kiersbilck et al	Internal
6,652,470	Using image modification and temperature biofeedback to diagnose and treat ADHD	Eastman Kodak	Patton et al	Internal
6,896,655	System and method for conditioning the psychological state of a subject using an adaptive auto stereoscopic display	Eastman Kodak	Patton et al	Internal
	Eastman Kodak Count	4
	Grand Count	6

This is just the citation of a single patent. When a portfolio of patents is analyzed the results can be very illuminating, telling which patents are most popular and which competitors are using them for what purpose. A goldmine of competitive intelligence can be found in a well done portfolio citation analysis.