March 11, 2026 M1 Part 2 – our provisional answers

As already mentioned in the blog post about M1 Part 1, there were no benchmarkers for M1 this year so we had to do the paper after you did it (and benchmark B in the meantime). At DP, Sander, Wouter and I did the paper and some of you were so kind as to send us your answers, so I took a sneak peak at those as well – after I did the paper of course!

I saw quite a lot of variation in the amended claims, in terms of how broad was claimed but even claims going in different directions, based on different interpretations of the prior art and of the description.

From our internal discussion I concluded that different answers are defendable. The good thing about M1 Part 2 is however that it is a free text paper so you can explain why you made the choices as you did, and your interpretation of e.g. the prior art shines through. I hope this allows the Exam Committee to award points also to solutions that may have not been foreseen or intended, but were properly argued and/or explained.

 

So, first of all, the amended claims. I think it is defendable to have the following claim 1:

1. A hydrocolloid plaster comprising:
- a carrier film; and
- a hydrocolloid layer on the carrier film,

wherein the hydrocolloid layer comprises pectin.

This claim is novel in view of D1 and D2 as those do not disclose pectin. However, you could argue that it is not novel in view of D3, but this seems to be up for interpretation.

The argument for lack of novelty of this amended claim in view of D3 would be that the cling film of D3 would be the carrier film and that the jam with the pectin would be the hydrocolloid layer comprising pectin. After all, the definition of hydrocolloid as given in line 9 of page 2 of the paper (“a material that forms a gel when it mixes with water”) matches with what the paper tells us about pectin (line 27 of prior art page: “forms a gel when it mixes with water”).

The debatable part of this line of argumentation is the point whether D3 actually discloses a hydrocolloid plaster. According to the application as filed, a plaster is “an adhesive, protective covering (such as a sticker or patch) that is applied to skin and can be used as a dressing to treat wounds or skin conditions such as blisters, minor burns, corns, calluses, or acne.” The question than is whether a piece of cling film with a dollop of jam on it is suitable for applying to skin as a dressing to treat wounds or skin conditions. I think arguments can be made both ways.

However, in view of that this is a paper aimed at people who have two years of experience, and who have only 90 minutes to solve the paper, I would say that the interpretation of D3 disclosing the amended claim as above would be too far fetched, in particular because there was no hint in for example the EESR to direct candidates in that line of thinking. But on the other hand, why else would D3 so explicitly refer to pectin forming a gel when mixed with water and to cling film?

If you interpret D3 as disclosing all features of the amended claim 1 as above, your amended claim 1 could for example be:

1. A hydrocolloid plaster comprising:
- a carrier film; and
- a hydrocolloid layer on the carrier film,

wherein the hydrocolloid layer comprises pectin, CMC and at least 10% weight/weight (w/w) pectin.
In my opinion both claims should get full marks as long as the defence for novelty is well argued and makes clear how the prior art documents were interpreted.

I have also seen an amended claim going in an entirely different direction, with as additional features that the plaster is suitable for treatment of blisters and is shaped for better adhesion to the heel, toes or sole of the foot. The basis and novelty of such a claim is defendable as well.

Something that I thought about was to replace the hydrocolloid plaster in claim 1 by something along the lines of the definition given in the first paragraph of page 2 of the description. I decided against that because that would require quite a bit of rephrasing of the words of that paragraph, which I think is beyond of what can be asked from a candidate with two years of practical experience.

For the dependent claims, multiple options were available, for example the combination with the salicylic acid and the specific percentage thereof. However, be careful not to claim something like the use of the hydrocolloid plaster for treating wounds, as that would be against Art. 53c EPC.

Basis for the amendments including pectin can be found in lines 15-18 of page 2 of the application as filed. If you are of the opinion that D3 does not disclose a hydrocolloid plaster, then there is no need to limit your amended claim 1 to also comprising CMC and ant at least 10%(w/w) pectin, as the first sentence of this paragraph gives basis for including just pectin as a feature.

Then moving to the question which document is closest prior art. Both D1 and D2 are clearly in the technical field of hydrocolloid plasters, and I can imagine that deciding between those two might have caused some significant thinking. I decided to go for D1 because the hydrocolloid plaster of D1 is designed for healing by absorbing fluid (third line of D1), just like the hydrocolloid plaster according to the invention (see line 11 page 1 application as filed. So, D1 has the same purpose as claim 1. What made me turn away from D2 as CPA was that it focuses on the technical effect of the salicylic aced and not so much on the effect of the hydrocolloidal layer.

In view of D1, the distinguishing feature is the presence of pectin (broadly claimed or more limited). The technical effect of pectin is that it speeds up wound healing time (see line 17 page 2 application as filed). None of the prior art documents discloses that pectin has this effect.

As for question 5, whether or not a divisional was needed for protection for other product lines such as wound dressings, of course it matters how you formulated the amended claim 1. If you there had made the choice to go in the direction of adding pectin, then you can argue that no divisional is necessary because the wound dressing is already included in the definition of what a plaster is.

However, if you went into the direction of amending your claim 1 in the direction of it being to suitable for the treatment of blisters and to suit the shape of the foot, then your advice will be different.

Then question 6, with respect to the question of the client relating to the gelatine-only variety of the plasters. That one got me really puzzled. Of course it is clear that you cannot add such claims to the current application as there is no basis in the application as filed.

But then, whose invention is this gelatine-only plaster? To be honest, I don’t know…

Take the first two sentences of the last paragraph of the client’s letter. They read:

“Our main competitor has recently started selling a new type of hydrocolloid plaster. We can see from the product information leaflet that it is exactly the same as ours, except that the hydrocolloid layer contains only gelatine.”

Now whose plaster contains only gelatine, our plaster or the plaster of the competitor? That makes a big difference for the answer. If the gelatine-only plaster is ours, we can file a new application for it. However, if the gelatine-only plaster is the product that is already sold by the competitor then it makes no sense to file a new application for it because 1) it would not be novel and 2) our client did not invent this.

I checked the answers that I received from candidates, and it is literally 50%-50% in terms of the interpretation of the information in the paper in this respect. Therefore, both should awarded with an equal amount of points in my opinion. I’m really curious to hear in the comments how you interpreted this!