Aerotel v Wavecrest  EWCA Civ 408
Jacob, Richards, Sullivan LLJ in the Court of Appeal heard an appeal from JJH Fysh QC, sitting as a Deputy High Court Judge. JJH Fysh had found Aerotel’s patent invalid for obviousness. The patent related to a system for telephones and a method for making calls.
A large part of the appeal revolved around the commercial success it had with the patent, arguing that this showed lack of obviousness, in summary, because if it was obvious everyone would be doing it, and there would not be such commercial success.
The appeal was dismissed. The invention was obvious. The Deputy Judge had not erred in principle.
While the commercial success of an invention can be a powerful indication of non-obviousness if it is shown that the alleged invention has led to commercial success, here Aerotel had not shown that its commercial success was due to the invention. Rather, it had made money from the patent by litigation and the threat of litigation, principally in the US. Aerotel were able to point to the fact that there had been an increasing business in prepayment telephone cards from a certain date. However that was not enough to prove that the invention as disclosed and claimed in the patent was the cause of that business.
A patentee seeking to rely on commercial success as an indicator of non-obviousness had to establish that the commercial success relied on was due to his invention and not to other market factors. The evidential onus of proof is on the patent owner, and the party making the allegation was not required to show that the commercial success was due to other factors.
JACOB LJ said that the commercial success of a patent could be a powerful indication of non-obviousness if it was shown that the alleged invention had led to commercial success. The question ‘why was it not done before?’ he said as compelling if there was no adequate answer. Many other factors would have been at work. There had been ample evidence on the facts upon which the deputy judge could base his conclusion that the case on commercial success had not been made out. There had been no dispute as to the test for obviousness set out in Pozzoli v BDMO  Bus LR D117. The claimant had failed to identify any errors of principle made by the deputy judge.