Interpreting patent claims and the meaning of “dry frier”Print publication
The High Court case of Jarden Solutions (Europe) Ltd v SEB SA  concerned a dispute about deep fat fryers.
SEB had a European patent for a “Fryer with automatic fat coating” which it claimed was infringed by Jarden’s import and sale of a different fryer. The competing fryers operated in a broadly similar manner, by stirring and turning the food to coat it with a thin film of oil while cooking the food by means of a flow of heat from above. Jarden denied infringement and sought revocation of SEB’s patent on the basis of the prior art.
The patent claimed a “dry fryer” and the first part of the judgment tackled the meaning of this term. Jarden argued that the term included a “shallow fryer”. SEB denied that it included a shallow fryer. Having explained the difference between deep fat frying and shallow frying and the concept of “dry frying”, the judge agreed with Jarden’s interpretation of the term “dry fryer”.
This was crucial as this meant that the prior art disclosed a dry fryer and that the main claims of SEB’s patent were not obvious over the prior art.
The judge went on to find that, although the main claims of the patent were obvious, subsidiary claims were valid and had been infringed. (The judge reached this conclusion after having listened to the experts, watched cooking demonstrations and himself tried out the allegedly infringing products). The prior art in respect of the subsidiary claims was not such as would have been consulted by a team skilled in the art.
The case is instructive for showing the approach the courts will take to the issue of claims construction and obviousness in what is a fairly every-day context.
 EWHC  445 (Pat)