Griffith Hack Report

Griffith Hack, an Australian firm specializing in intellectual property, conducted an independent analysis of 58,000 hybrid vehicle patents in 2009-2010 and identified the 10 most important hybrid patents in the world. Paice patents ranked as most important, with four of the top 10 patents and three of the top four spots. No other company had more than one patent ranked in the top 10.

From the report:

Network Patent Analysis is the sophisticated analysis and mapping of patent citation data for the purposes of determining the leading patents, patent applicants and technology trends in any area of technology.

Analysing 58,000 hybrid car patents and their inter-relationships, we found that the top ranked patents were filed by the hybrid drivetrain developer Paice Corporation, ahead of patents filed by Toyota, Ford and Honda who are better known for selling hybrid vehicles.

The leading Paice hybrid car patents were shown to have strong self-citation relationships with other Paice patents. This contrasts with the top ten hybrid car patents filed by Ford, which were connected via citations to a variety of companies including Paice, Toyota, and Railpower Technologies, who have developed hybrid technologies for trains.

View the Griffith Hack Report

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Top 10 Hybrid Vehicle Patents

• 1. Paice (6,209,672) Issued 1998

  Hybrid car with two electric motors, one connected to engine and one connected to car wheels

• 2. Paice (5,343,970) Issued 1992

  Improved hybrid electric vehicle where both engine and electric motor power the car, and energy is captured via regenerative braking

• 3. Equos Research (5,806,617) Issued 1995

  Control system for combining electric and motor power in transmission

• 4. Paice (6,338,391) Issued 1999

  Electric motor coupled to turbocharged motor, and control system

• 5. Hybricon (4,351,405) Issued 1978

  Engine driving one set of wheels, and electric motor partially powered by regenerative braking driving the other set of wheels

• 6. Toyota (5,428,274) Issued 1991

  Control system for electric motor powered by internal combustion motor or battery

• 7. Paice (6,554,088) Issued 2001

  Hybrid only runs engine when high torque needed

• 8. Ford (5,264,764) Issued 1992

  Controller for requesting an engine driven generator to top up the vehicle battery

• 9. Hitachi (6,470,983) Issued 1999

  Controls battery level on hybrid drive according to navigation plans of drive

• 10. Honda (6,943,460) Issued 2002

  Control system for a hybrid car including cylinder deactivation