Thursday, March 12, 2026 Paper C 2026 – our provisional answer.

 

Today was the last EQE exam in the format that we are all used to. They chose a particularly nice paper to finish off with. Nyske, Nico, Joeri and I did the paper; our answers were all the same. Part 1 was a bit easier than Part 2, which had a few more unusual features. Time wise, the paper seemed doable.

 

Part 1

Claim 1 was directed to a device for purifying air. We attacked it under inventive step starting from the Sondy Purifier Cool, which was sold in spring 2019 and shown in A2. The missing feature is the use of sound insulation material which is disclosed in A4.

Claim 2 is dependent on Claim 1, but since it has a priority loss, we have the additional document A3. Claim 2 is not novel over A3. An interesting aspect is that Claim 2 is directed to a “Device for purifying air” while A3 discloses a “vacuum cleaner”.

Can we regard a vacuum cleaner as an air purifier? We think yes, for two reasons. First, A3 mentions that it removes dust from "air containing dust", and so air is purified. Second, A1 makes a distinction between a “device for purifying air” and an “air purifier”. The latter is just an example of the former. So A1 also sees the claim category device for purifying air as broader than just air purifiers.

Claim 3 depends on Claim 2 and also has a priority loss. This allows one to continue the novelty attack as an inventive step attack, starting from document A3. We end up with two distinguishing features; one is the type of particles in the sound insulation material, and the other is an optical navigation unit. They do not have a synergistic effect, and so we can use partial problems. The sound insulation particles we got from A4. The optical navigation unit comes from A5.

 

Part 2

In Part 2 we get a new document, A6. Note that the applicant of A6 is the same as the opponent of A1. It is easy to mistake this for a potential first application situation. Fortunately, even if you fell for this, the first application issue does not pan out, as A6 does not disclose any of the Part 2 claims.

Claim 4 was one of the harder attacks to find. The available documents for Claim 4 are: A2, A4, A5, A6, and A7. Starting from A2 will not work, as the Sondry Purifier Cool is not related to dust and seems too heavy to turn into a mobile device. A4 is tempting, as it has a pet robot that measures dust concentration. However, the pet robot is not a moving air purifier and cannot be adapted into one—the device is too small, and the sensor is not compatible. A5 is in the wrong field—humidification instead of air filtering—so it cannot be used as a starting point. A7 does not disclose a sensor. That leaves A6 as a starting point.

A6 measures dust concentration using sensing stations, and not in the moving air purifier. This is the same situation as in A5 but for humidifiers. A5 teaches moving the humidity sensor into the robot.

Claim 5 can be attacked starting from document A4. The final two features of Claim 5 are not disclosed in A4:

- generating a virtual map of the dust concentration in the indoor space;

- causing a screen of a user interface to display the generated virtual map

 

These features do not serve a technical purpose. In particular, the user does not use the map to control the device. Merely computing information, even if displayed, that does not serve a technical purpose cannot make the claim inventive—this is G 1/19.

 

Claim 6 turns out to have the same distinguishing feature as Claim 5 when starting from A4, so it is not inventive for the same reasons.

 

Claim 7 has an optional feature. The client instructs us to attack both versions. Claim 7 without the optional feature is not novel in light of A7.

Claim 7 with the optional feature is more difficult. The optional feature is to recharge “when the battery level is below a first threshold, the first threshold being 20%”.  Starting from A7, the problem of extending battery life leads us to A3, which teaches recharging at 18%.

A wrong argument for dealing with Claim 7 would be to say that, since the obvious combination of A7+A3 charges at 18%, and 18% is below 20%, a point within the range of Claim 7 is disclosed.

This is incorrect, since the correct interpretation of Claim 7 is that charging starts as soon as the battery level is 20%. This must be the required interpretation, since otherwise recharging at, say, 1% would also fall under Claim 7. Such an interpretation would not have the effect of avoiding deep discharge, so this cannot be what is meant.

Thus, we are not done yet after combining with A3. The correct approach would be to notice that 18% is different from 20%, but that the values are close and the technical effects are the same. The skilled person would optimize the exact threshold for A7 as a workshop modification.

 

Claim 8 contains the feature “to recharge when the battery level is below a first threshold or when a measured dust concentration is below a second threshold”. Although this looks like an or-claim, the intended reading of Claim 8 is that we have a single device triggered for recharging when either condition is met. It is also possible to read Claim 8 as covering two devices: one in which recharging is triggered by battery level, and one in which it is triggered by dust concentration.

The intended reading is added matter in its entirety. The alternative reading would need two attacks: one is the same as the attack on Claim 7, and the other is added matter.