A Suffolk farmer-inventor has expressed deep disappointment after losing a long-running patent battle over one of his seed drill designs.

Seed drill makers Claydon Yield-o-Meter Ltd — run by Jeff Claydon at Wickhambrook, near Newmarket — claimed that rival company Mzuri’s Pro-Til and Pro-Til Select single pass drills infringed its UK and European patents.

But Mzuri successfully argued in court that the seed drill patents were invalid — partly because of prior use of the design in public when a prototype was tested out in a field.

Mr Claydon warned the judgement in the case of Claydon v Mzuri would stifle innovation and have unintended consequences while Mzuri welcomed the judgement — which followed a three-day court hearing in May and a three-year-long legal wrangle.

The defendant (Mzuri) argued there was potential for prior disclosure during testing of a new type of seed drill. Claydon argued testing of the new drill had taken place on private, secluded farmland owned by the company’s directors next to its factory in Suffolk.

Mzuri said there no infringement of the claimant’s patents due to lack of inventiveness as well as the inline tines design being used in public prior to the patents.

It claimed the concept dated back to much earlier seed drill designs anyway and arguments between the two parties hinged on whether the prototype could be seen from a public footpath as well as whether the Mzuri design actually infringed any patents. The judge in the case — His Honour Judge Hacon — concluded that a skilled person would have been able to deduce all the claimed features of the invention from the edge of the 40-acre field.

Mr Claydon claimed the outcome of the case hinged “entirely on a technicality which we consider to be unjust”.

“This was based on a completely hypothetical situation. What “could happen” and what actually “did happen” are two totally different things. In other areas of law, you need evidence that something actually “did happen” and without that the case does not stand. In my opinion, patent law should be no different,” he said.

“The decision represented a sad day for patents and innovators as it makes it virtually impossible to test any invention outdoors, something which is necessary for agricultural machinery.

“Without reward there is no incentive to innovate, and without innovation there is no progress to create better, more efficient equipment and processes.”

Martin Lole — the Worcestershire farmer-engineer who heads up Mzuri — described the “lengthy and costly” court case as “entirely avoidable and detrimental to agricultural innovation in the UK”.

“We have been disappointed to have been the target of a court case brought about by another British manufacturer which sought to claim damages and prevent us from selling our flagship product into the market,” he said.

“Single pass technology such as one tine in front of another has been around for many years, even documented by early innovators such as Jethro Tull and has been popular (particularly in the US) for some time prior to the patent priority date. We have always maintained that we do not infringe the Claydon patents.”