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Tales from an expert witness: Prior art and patent trolls

Where ideas, inventions and opportunists collide

Rigorous arguments

In my experience the majority of patent disputes don’t get as far as a court. The court is usually only involved where matters such as pride and loss of face predominate over logic. So the goal is usually to establish what the true position is. So whilst it may not actually happen, everything an expert does has to be done to a level of diligence that will stand up in the event that it does end up in court. And woe betide any expert who has not worked to that level of diligence.

It’s not a pretty sight watching experts being taken apart by QCs.

On the other hand, things are what they are, and if you have come to tell the court how things are, how sure you are and why you are so sure, then no matter how aggressive the cross examination, you and what you have come to say will survive.

Legally Blonde (2001)

"Isn't the first cardinal rule of perm maintenance that you are forbidden to wet your hair for at least 24 hours after getting a perm at the risk of de-activating the ammonium thiglycolate?" Source: MGM Legally Blonde

So I no longer have any beliefs or opinions, but I am aware of some facts that I can back up with any number of peer-reviewed references and indeed derive from the laws of physics, if need be.

I have no doubt that the level of rigour required in litigation has brushed off into my other endeavours and that has been wonderfully helpful in areas as diverse as writing, design and fault finding. Certainly doing things properly once is a lot more efficient than doing it over and over again.

Another one of my experiences is that on a number of occasions where manufacturers are accused of infringing a patent, the accusation comes from an organisation that buys the rights to patents en masse and then looks for a manufacturer who will pay royalties to avoid litigation. Of course, once those royalties are being paid, funding exists to allow more litigation and so on. When I was first involved in this sort of thing, it didn’t have a name. Now it’s called patent trolling and it is disturbingly widespread.

Patent place

Patent Place: for some companies the soap opera looks set to continue for a few more seasons

Patent Trolling

Trolling works by accusing multiple organisations of infringement. The solution is for those organisations to locate one another and co-operate. In one instance I was acting as the expert for one client and I discovered the prior art that invalidated the patent held against them. My client did nothing but quietly passed on the prior art to another firm that was being accused of infringing the same patent. That firm’s patent agent successfully applied to have the patent invalidated, which brought all of the troll’s actions to a halt.

Thus one of the jobs of an expert is to help with the assessment of the validity of patents held against his client. This is where a long experience in the relevant subject matter pays off. I think my record for finding the prior art that invalidated a patent was 5 minutes, my worst was 5 months.

Do Not Adjust Your Set

The Japanese took a different line with PAL, albeit a bit fuzzy

The former was quite amusing because the accusation of infringement was made by a division of a Japanese company. I was able to find on my bookshelf a document which anticipated the patent concerned. It was published by another division of the same Japanese company.

In this case the moral is that organisations that apply for patents need to be a little bit careful about what they publish in case they shoot themselves in the foot, as was the case here.

On the other hand the way in which a patent is written can leave the inventor vulnerable. A classic case is that of the Japanese TV sets that could receive PAL TV signals without infringing the PAL patents, because they simply decoded every other line, in the same way that an NTSC set decodes, and ignored the ones between. The phase alternating process of PAL was simply not performed, so there was no infringement. There was a minor loss of quality, but no royalties had to be paid.

The Secret of Success

Another one of the things that I have learned over the years is that once something becomes successful everyone and his dog claim to have invented it or some part of it.

I saw it with the Compact Disc and I saw it with digital television.


Compact Disc v. vinyl: Joop Sinjou, Head of CD-Lab in 1979

It was in connection with the former that I had my worst nightmare. This was a patent held against some CD manufacturers that claimed a method for detecting the synchronising pattern at the beginning of a data block. The patent had been granted to some student of an American technical college, who genuinely thought he had invented it because he hadn’t done any research.

The fact that the patent was granted is harder to explain. I knew full well that every mass storage device I had ever come across, from drum stores onwards, used such a system, but because it was so normal and widespread, no-one had thought to document it and there was no prior art to be found.

Eventually I found exactly what the patent claimed in a document supplied to the US military during the Cold War. This was the maintenance manual for an obscure piece of equipment that had to explain everything for contractual reasons. Days later the Patent Agent involved applied for invalidation, the CD manufacturers saved themselves about six million dollars – and I bought a helicopter. Those were the days.

The impression made by the original Philips patents for optical discs have stayed with me as examples of robust and well written documents. The novelty of the Philips discs was to use phase contrast, where the entire surface of the disc has the same finish and no conventional contrast exists to read the data. Instead the data are described by parts of the disc surface that are shifted by a quarter of a wavelength so the light has travelled half a wavelength more or less and cancels out.

Phase contrast microscopes were known, scanning microscopes were known, and data storage on discs was known, but to use a phase contrast scanning microscope to read information on a disc was an invention. One of the best guides for inventiveness is that all of the ingredients were readily available, but no-one had previously thought to combine them in that way. ®

John Watkinson is a member of the Society of Expert Witnesses and is listed in Who’s Who in the World.

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