Facts Decision Comment

SEB SA's Actifry patent has been the subject of numerous invalidation requests. In a September 2015 decision, the Patent Re-examination Board recognised the invention as a technological breakthrough and maintained the patent's validity. According to publicly available records, this was the first time that the board based its decision in a patent invalidity proceeding specifically on the concept of breakthrough technology.


In 2005 SEB SA filed Patent CN200580018875.3 in China for a "fryer that can automatically coat the food with oil". The patent was granted in 2009. Actifry, the patented product, heats food via hot air flow and simultaneously uses a paddle to mix oil with the food – most commonly, potato chips. The rotation of the paddle helps the food to heat evenly. The patentee created the term 'dry fryer' to describe the technology. Compared with prior art, the fryer uses less oil and is more efficient. The patented fryer became a great success in the global market, with accumulated sales amounting to over 7 million units.

Since 2009, numerous Chinese competitors have tried to use the patent. In response, SEB SA has filed lawsuits, against which six invalidation requests were filed by 2015. The board heard the three most recent invalidation requests in one March 2015 hearing.

The applicants cited 13 existing technologies, mostly dating from the 1960s to the early 1990s. The technologies involved heating via air flow and various ways of mixing food with oil, such as:

  • using a rotating basket with the base immersed in oil;
  • spraying fine drops of oil on the food; and
  • coating the food with oil before heating.

However, none of the cited prior art included a device that could mix food with oil and simultaneously turn the food evenly during the heating process. The petitioners of invalidation alleged that using a paddle to mix the food with oil was an obvious solution (common knowledge).


In its response, SEB SA argued that dry frying is a revolutionary technical solution compared with prior art. The technical effect was not achieved by simply combining the existing prior art, as the petitioners alleged. SEB SA argued that, in evaluating the inventiveness of the patent, the board should not look for prior art relating to each technical feature mechanically. Rather, it should fully examine the prior technologies and the patent's technical solution and contribution to the prior art as a whole. Dry frying technology was a breakthrough compared with prior cooking methods. The direct impact of hot air flow on food could quickly dry its outer layer, while the mixing device could coat it with a thin layer of oil and turn it for constant and even heating. SEB SA argued that dry frying achieved the effect of traditional immersion frying, but used significantly less oil and caused little pollution, solving a long-term industry problem. The popularity of the patented product and the numerous infringements of the technology proved the patent's value and inventiveness.

In September 2015 the board held that the invention was a technological breakthrough compared with prior art and maintained the patent's validity.


Under Article 22 of the Patent Law, to qualify as 'inventive' an invention must – compared with existing technologies – have "prominent and substantial features" and constitute a "remarkable advancement". Chapter 4, Part 2(1) of the Patent Examination Guidelines includes six patent categories, the first of which is breakthrough patents. This refers to patents pertaining to a new technical solution that has no precedent in technical history and signifies a new era in technological development. This kind of patent has the highest level of inventiveness, examples of which include radar, laser technology and the radio.

In this invalidation case, SEB SA argued on the method for evaluating the inventiveness of the product, the long-felt need for it and its commercial success, convincing the board that the patented product was a technological breakthrough. Such recognition will enhance SEB SA's ability to protect the patent in enforcement proceedings.

For further information on this topic please contact Shuhua Zhang at Wan Hui Da Law Firm & Intellectual Property Agency by telephone (+86 10 6892 1000) or email (zhangshuhua@wanhuida.com). The Wan Hu Da Law Firm & Intellectual Property Agency website can be accessed at www.wanhuida.com.

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