The Adidas watch that checks your pulse: patent classification problems

There has been a lot of publicity about wearable technology that diagnoses you -- checking your heartbeat or pulse and so on.

When I first heard of this idea I thought of shirts incorporating technology, but most of the interest is in wristwatches. An example is in Adidas' new sensor for athletes, so that training programmes can be planned, and there is a BBC news story on it, Adidas Micoach smartwatch has heart-rate sensor

Now, supposing you wanted to identify inventions by Adidas in that field. You could ask a patent database for Adidas plus keywords such as watch. Better would be to take the patent classification A61B5/024, "Detecting, measuring, or recording pulse rate or heart rate."

This is an IPC -- it will be used by patent offices when they publish patent specifications. A61B5/02438 is a CPC which is a more precise class, not used on the specifications but added to those published by leading Western nations plus the World PCT system. It is for portable devices worn by the patient (or any user, really). It might seem obvious to use that class combined with the company name but it is easy to miss material, so while any detailed search would certainly use it, a second search should always be used with the broader class plus keywords.

Let's call using A61B5/024 for Adidas Search 1, and A61B5/02438 Search 2.

It is still necessary to decide which search box in Espacenet you use: CPC or IPC. The results below give first CPC and then IPC for Search 1 (Search 2 doesn't have an IPC option, as it is not a valid class).

Search 1 gives in CPC 4179 hits, with 2 by Adidas; in IPC 7127 with 5 by Adidas.

Search 2 gives in CPC 3129 hits, with 4 by Adidas.

How can this be ? The apparently broad search found fewer hits by Adidas as CPC, but more with the IPC than the apparently more precise CPC.

Besides the fact that the company may be working in related fields, and double-counting when more than one entry appears for the same invention, a problem is that using simply A61B5/024 says that only that class is wanted. Any specification classified by a more detailed class instead is missed.

Espacenet deals with this problem by allowing anyone searching the classification to enter the class in the search box which automatically selects the subordinate classes. They can then be copied to the search form. This results in a CPC search which we can call Search 3.

Search 3 gives in CPC 12,925 hits, with 7 by Adidas.

These include the intriguingly named Method and system for extracting cardiac parameters from plethysmographic signals, illustrated below.

Six of the seven are for similar coats that do the monitoring etc., while the seventh is not obviously for a watch -- it is a "portable electronic unit" which monitors congestive heart failure patients, and hence obviously not athletes.

So which is the best approach ? If asked to search for inventions for the concept by Adidas, I would use broad classes in both CPC and IPC (as the company has relatively few inventions). I would use the "In my patents list" ability (below the title in the bibliographic format) to list patent specifications by Adidas in the general field for later retrieval. I would also use the descriptions and the search reports at the end of European or World publications to see if they mentioned related material by Adidas.

I also searched the very broad A61B together with timepiece, watch and wristwatch (and their plurals) for Adidas and got zero hits (but beware their clever use of "portable electronic unit", which includes most watches).

It does seem that Adidas has not yet published the details -- hardly surprising, as it takes 18 months for a new specification to be published.