Honeywell’s HFO-1234yf patent revoked in Europe

By Jim Taylor, Editor MACS ACtion Magazine
After oral proceedings on March 27, a three member panel of examiners at the European Patent Office (EPO) revoked Honeywell International’s patent on a family of chemicals that includes HFO-1234yf and its use as a refrigerant In automotive air conditioning systems. The decision concluded a six-year saga that brought opposition to the patent from many other companies and generated more than 800 documents. The company has already appealed the decision.

The patent in question originated in 2005 when Honeywell was issued a European patent for “…compositions comprising at lease one fluoroalkene containing from 3 to 4 carbon atoms, preferably three carbon atoms, and at least one carbon-carbon double bond. The fluoroalkene compounds are sometimes referred to…for the purpose of convenience as hydrofluoro-olefins or “HFOs” if the contain at least one hydrogen.”

In the patent world not only must the chemistry and process be specified but also the intended use(s) of the product. In this case, the company noted that variants of the chemical are useful for “heat transfer, foam blowing, solvating, flavor and fragrance extraction or delivery, and aerosol generation.” The initial patent was issued after a standard review by the EPO.

In 2006, Honeywell sought to amend the patent by adding additional details and new specific uses, including one variant, HFO-1234yf specifically for vehicle air conditioning. This started a multi-year back and forth exchange between EPO and company as various clauses needed revision or had to be brought into conformity with patent law. Since the discussion was between the patent owner (called Proprietor) and the EPO, others couldn’t object but they certainly were watching.

The amended patent was published in November, 2009 and in late January of the next year, Arkema France filed the first formal objection to the patent. By the end of that year they had been joined by Daikin Industries, Asahi Glass Co., Daimler AG, ACEA, BMW AG, Mexichem, Solvay Fluor, and high-profile European patent attorney Michael Wallinger; all filed individual formal objections with EPO.

Documents flew thick and fast, and the proprietor offered more amendments to the patent, trying to dial it in to an acceptable level. The main points made by the opposition were that the added subject matter wasn’t mentioned in detail in the original, the entire patent “lacked novelty” as most of the methods and uses were already known to “those skilled in the art,” and that the whole patent had a “lack of inventive step(s).”

Finally EPO called for Oral Proceedings in March of this year. It’s not a trial as such, but more of a hearing before a panel of examiners who attempt to untie the knotty questions via the many laws and regulations in effect. Although three days were allotted for the Orals, by the end of the first day the tribunal had made its decision.

”The patent is revoked under Article 101(2) EPC as at least one of the grounds of oppositions prejudices its maintenance unamended, and under Article 101(3) (b) EPC because taking into account the amendments made by the proprietor during the opposition proceedings, the patent and the invention to which it relates do no meet the requirements of the EPC.” (European Patent Convention)

Two days later, Honeywell filed a Notice of Appeal and requested that the panel’s decision be overturned.


The Mobile Air Conditioning Society’s blog has been honored as the best business to business blog in the Automotive Aftermarket by the Automotive Communications Awards and the Car Care Council Women’s Board!

When having your mobile A/C system professionally serviced, insist on proper repair procedures and quality replacement parts. Insist on recovery and recycling so that refrigerant can be reused and not released into the atmosphere.

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The 33rd annual Mobile Air Conditioning Society (MACS) Worldwide Training Conference and Trade Show, Be the Best of the Best will take place February 7-9, 2013 at the Caribe Royale, Orlando, FL.


About macsworldwide

Mobile Air Conditioning Society (MACS) Worldwide Founded in 1981, MACS is the leading non-profit trade association for the mobile air conditioning, heating and engine cooling system segment of the automotive aftermarket. Since 1991, MACS has assisted more than 600,000 technicians to comply with the 1990 U.S. EPA Clean Air Act requirements for certification in refrigerant recovery and recycling to protect the environment. The Mobile Air Conditioning Society (MACS) Worldwide’s mission is clear and focused--as the recognized global authority on mobile air conditioning and heat transfer industry issues.
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