Sugru

The UK IPO have recently been promoting via Twitter a video commissioned by them about a company known as Sugru. The company (which is actually called FormFormForm Limited, but I will use the short form) has developed a kind of settable Blu-Tack that can be used for all kinds of fixing and mending jobs. I have bought some myself and can confirm that it does work as advertised and is pretty handy. Most of the little packets of Sugru I have are, however, I suspect destined to live in that drawer everyone has somewhere in the house for things that don't have another place to live.

In the video, the founder of the company Jane Delahanty and her business partner Roger Ashby discuss how and why they went about getting IP protection for their invention. They mention that they had "invested heavily" in intellectual property protection and that a top quality patent attorney was vital. They also mention that their trade mark was a very important part of their IP strategy. Roger points out that a weak patent would be not worth the money involved in getting it. This got me interested in finding out what exactly Sugru had managed to get patented via their top quality patent attorneys, who shall in this post remain nameless despite the rather shameless plugging they get in the video (paid for, of course, by the IPO). I will leave it to the reader to find out who they are.

Looking at the European patent register, there are three applications in the name of FormFormForm Limited: EP06743997 for a "Mouldable Material"; EP06744002 for a "Hand-Mouldable Material"; and EP07824749 for a "Room Temperature Curable Silicone Elastomer Composition". The first two claim priority from two GB applications filed in 2005 and the last one to a GB application filed in 2006. Espacenet shows that there are two distinct patent families here and here, which also cover applications in the US, China and Japan. So far, there are only two granted patents: EP2089465B1 and CN101616979B, granted in 2012 and 2013 respectively, both in the latter family of applications. The other two European applications have been deemed withdrawn, one due to non-payment of a renewal fee and the other due to no response being filed to a notification of allowance. The latter withdrawal seemed strange, so I took a quick look at the allowed claims, which define a two-part silicone elastomer composition. Presumably this is not what Sugru were interested in any more, as the product is a one-part elastomer, so the application was probably dropped for this reason. The first family of applications therefore looks pretty much dead.

The later European application has an interesting history. It was originally filed, as a PCT application, with the following rather brief (and very broad) claim 1:

1. A one part room temperature curable silicone elastomer composition where the uncured composition has a Williams plasticity from 80 mm to 900 mm.

The measure of plasticity seems to be an industry standard, particularly for measuring the plasticity of silicone materials. The test is quite simple, basically involving a measure of how much a pellet of material will plastically deform under a dead weight over a set period of time (using a simple machine like the one on the right, available here). A lower number indicates a greater degree of plasticity. The lower threshold of 80 mm in the claim indicates that the composition would be somewhat resilient rather than being completely plastic, as it does not flow completely away under a load. The upper bound simply indicates that there is some plasticity, as a zero plasticity material would bounce back to its original shape (giving a value of 1000 mm). So far, so good, although such a broad claim would immediately raise suspicions that it might not be novel, given there is a lot of prior art on silicone elastomers, which anyone familiar with the field would be aware of. One might therefore expect to see a lot of generalised fall back positions in the dependent claims and elsewhere. Surprisingly, however, there were only 9 dependent claims in the original application, four of which merely provided further narrowed ranges for the plasticity values.

Unsurprisingly, the EPO examiner found that the invention was not new, citing various prior art documents including this one from Dow Corning (a big player in silicones). In the written opinion of the international searching authority, the examiner found that claim 1 was not new over seven different documents. The applicant, via their attorneys, disagreed and argued that none of the documents in fact showed compositions having plasticity values in the claimed range. The examiner was not convinced by this and issued a summons to oral proceedings (a bit premature perhaps, but probably justified in this case). An interesting feature was that the examiner put the onus on the applicant to show "by appropriate comparison tests that the uncured composition characteristic differences do exist with respect to the Williams plasticity" (annex to the summons, 4 March 2011). The applicant's attorney argued against this, but made extensive amendments to the claims anyway and did not provide any comparison data. After arguing the case at the oral proceedings, with Ms Delahanty accompanying, the examining division finally agreed on the following claim:

1. A one part room temperature curable silicone elastomer composition where the uncured composition has a Williams Plasticity from 80 mm to 900 mm, and where the composition is a non-adhesive composition, the composition comprising:

20-60% by weight of a hydroxy-terminated poly(dimethylsiloxane) of viscosity greater than 350,000 mPa s (25°C) ;

3-66% by weight of a reinforcing filler;

10-60% by weight of a non-reinforcing filler;

2-6% by weight of a crosslinker;

and a suitable quantity of a curing catalyst.

I leave the reader to decide whether this is a claim that is worth spending a lot of money on, which Sugru must have done judging by the size of the EP prosecution history alone. I could certainly find a few fairly straightforward ways of looking at getting around the claim if I wanted to avoid infringing it.

The lessons to be learned from the Sugru case study, in my opinion, are not really those the IPO video would apparently like us to believe, i.e. that it is very important to get patent protection for your invention and worth spending lots of money on it. For Sugru, I think their most valuable IP is their brand, and not their patents. This might not have been obvious from the start, but has become clear over the years as their business has developed. After developing a formulation that works well, they have spend a lot of effort in marketing the product and have so far been very successful in doing it. Jane Delahanty's stated aim of Sugru being one of those things, like Blu-Tack, that everyone has in case they need something fixing, may be a plausible one and would certainly make them a lot of money if it came even partly true. Getting there does not, however, depend on having the patent that they managed to get.