Friday, December 16, 2016 T 66/12 - Simulation results and a sub-range

For people working in chemistry this may be just one of the so-many boards of appeal decisions on (sub) ranges. In the field of electro-mechanics I do not often see a decions about it.
In this opposition appeal the independent claim of the main request relates to a vehicle with a fuel cell. The independent claim comprises a sub range and the sub range seems to be the only difference with respect to the prior art. In the communication of the Board accompanying the summons to oral proceedings the Board concluded that the sub range is most probably an arbitrary specimen of the prior art and is, according to established case law, not novel. The final decision shows that the patent owner tried to prove that there is an effect in the claimed sub range. We can also read that the provided "simulations results" relate to current vehicles that may comprise technology that was not available at the date of filing of the current patent. Thus, there were no useful test results available at the date of filing to prove an effect of the sub range. This decision of the board shows what the consequence can be.

Reasons for the Decision

Summary of Facts and Submissions

[...] 

IV. With a letter dated 7 October 2016, and in response to a communication accompanying the summons to oral proceedings before the board dated 6 June 2016, the respondent filed anew the main request, together with five new auxiliary requests, and accompanied by simulation results indexed as enclosures 1 and 2a to 2e. 

[...]

VI. Claim 1 of the main request corresponds to claim 1 of the first auxiliary request underlying the decision under appeal, and reads as follows:

"A direct current power source comprising:

a pair of terminals that output electric power;

a fuel cell (40) connected to the terminals; and

an electric power storage device (20) connected to the terminals in parallel with the fuel cell,

characterized by

a DC-DC converter (30) connected between the electric power storage device (20) and the terminals,

wherein a ratio of a maximum output of the fuel cell to a maximum total output of the fuel cell and the electric power storage device is in a range of equal to or greater than 0.65 and equal to or less than 0.8."

[...]

VII. The appellant argued essentially as follows:

The simulations provided by the proprietor with the letter dated 7 October 2016 were late-filed and should not be admitted into the procedure. They were prima facie not clear and irrelevant. No information was given about the indicated weights and the reader had to guess about the meaning of the reported tests. The depicted curves did not show any clear range providing improved fuel efficiency. An objection of arbitrary selection had already been raised seven years ago. Test measurements could and should have been filed much earlier. It appeared that the tests were carried out using current technology, so that their relevance to the situation at the filing date of the application was not clear.

Concerning the last feature of claim 1 of the main request, the range indicated there not only did not fulfil the 3rd criterion (arbitrary selection) but also not the second criterion necessary for rendering the subject-matter of claim 1 novel. No normal range was known, and before deciding if a range was sufficiently removed from a known range, a normal range should be determined.

The other features of claim 1 were known from E1, in particular from claim 1 and column 3, lines 42 to 55, which defined the elements referenced 7 and 8 shown in figure 1 as constituting a DC-DC converter, and from column 3, line 28 together with column 4, line 20 which specified that the main and supplementary power sources could repectively be a fuel cell and a battery.

[...]

VIII. The respondent argued essentially as follows:

The filing of the supplementary document attached to the letter dated 7 October 2016 was a direct reaction to the board's communication. In this document tests concerning a variety of vehicle types were reported and it was clear that the reported tests led directly to the range indicated in claim 1 and shown in figure 5 of the patent. The range did not therefore result from an arbitrary selection.

The range indicated in claim 1 was also narrow compared to the possible range for the device shown in figure 1 of E1.

The range had to be appreciated also in combination with feature 3 of claim 1 which recited: "an electric power storage device (20) connected to the terminals in parallel with the fuel cell". E1 did not show a battery in parallel with a fuel cell. A complete circuit comprising windings 11 and 12 was inserted between the battery and the power terminals. Claim 1 specified also that the DC-DC converter was on the side of the battery and not on the side of the fuel cell. This contributed to increasing the fuel efficiency as recited in paragraph [0044] of the published patent. No parallel circuit of a battery and a fuel cell could be derived from the circuit diagram shown in the figure of E1. Furthermore the circuit of E1 was designed for allowing a supplementary source, like a flywheel, to supply power during peak power requirements and to receive power during braking phases, as recited in column 2, lines 42 to 48. This was a different approach from the present invention which foresaw a constant power provided mainly by a fuel cell and for a reduced amount by a battery, which was nonetheless capable of providing power for extended periods of time. For these reasons the power source of claim 1 of the main request differed from that disclosed in E1, so that the claim complied with the requirements of Article 54 EPC.

[...]
Reasons for the Decision

1. The appeal is admissible.

2. Main request

2.1 Admissibility of the simulation results filed with the letter of 7 October 2016

The simulations shown in enclosures 1 and 2a to 2e were carried out on five different vehicles. Characteristics of the vehicles are listed in enclosure 1 while each of enclosures 2a to 2e is dedicated to one of the vehicles and reveals a figure showing a fuel efficiency in km/kg versus an output ratio of a fuel cell to a battery, and a table showing different fuel cell output ratios with respect to vehicle weights. The figures show that the fuel efficiency is high for a certain range of fuel cell to battery output ratio. However, in each of the enclosures 2a to 2e the weight of the vehicle varies with the ratio, so that there is doubt as to whether the values reported in the figures of each of enclosures 2a to 2e relate to a vehicle of the same type and weight. The interpretation and explanation given by the respondent about the enclosures and in particular the tables did not convince the board that the simulations could be prima facie relevant for assessing if the range of output ratio defined in claim 1 was an arbitrary selection or not. In particular the graphs do not show clearly that the end points of the range (0.65 and 0.8) are significant, in particular since all the graphs show that the fuel efficiency varies little over a much broader range of output ratio. The results do not show that this range would apply generally, for instance when using different test cycles. Moreover, as noted by the appellant, the simulations seem to relate to current vehicles, so that it cannot be excluded that they make use of technologies which were not available at the priority date of the application underlying the patent.

Hence, taking into account the insufficient information derivable from the enclosures 1 and 2a to 2e, combined with the late point in time of their filing, the board exercised its discretionary power under Article 13(1) of the RPBA (Rules of Procedure of the Boards of Appeal) not to admit these simulation results into the proceedings.

2.2 Novelty - Article 54 EPC

2.2.1 E1 discloses a drive for an electrical vehicle comprising a permanent synchronous machine 3 connected to a converter 2 supplied over a direct current power source (see the figure). The direct current power source comprises:

- a pair of terminals 4a, 4b that output electric power,

- a fuel cell 6 (see column 3, lines 22 to 29) connected to the terminals,

- an electric power storage device 9 connected to the terminals in parallel with the fuel cell, and

- a DC-DC converter 7, 8 (see column 3, lines 42 to 44 and claim 1) connected between the electric power storage device 9 and the terminals 4a, 4b.

E1 does not give any information about the ratio of a maximum output of the fuel cell to a maximum total output of the fuel cell and the electric power storage device.

2.2.2 According to claim 1 the ratio is in a range of equal to or greater than 0.65 and equal to or less than 0.8.

2.2.3 According to the established case law of the boards of appeal, a definition of a (sub-)range can render the subject-matter of a claim novel only if it meets the three criteria defined in the decisions T198/84 and T279/89, namely that:

(a) the selected sub-range should be narrow;

(b) the selected sub-range should be sufficiently far removed from the known range illustrated by means of examples, and

(c) the selected area should not provide an arbitrary specimen from the prior art, i.e. not a mere embodiment of the prior description, but another invention (purposive selection).

2.2.4 In the light of the conclusion reached concerning the third of these criteria, the question as to whether the first two are satisfied can be left open.

2.2.5 The third of these criteria is not met, for the following reasons:

According to the respondent the claimed range of 0.65 to 0.80 was determined with the aim of improving fuel efficiency.

On page 5 of its reply to the grounds of appeal the respondent referred to paragraphs [0035] to [0042] of the patent specification to demonstrate that the results shown in figure 5 relating to a 10-15 mode and a vehicle of 2000kg were only examples and that "the output ratio of the fuel cell 40 and the battery 20 in view of the object of the present invention is independent on further values for obtaining the high energy efficiency."

However, further down the same page, the respondent acknowledges that "The lower limit of 0.65 for the output ratio of the present invention is set in accordance with passage 0037 [of the patent specification] in order to fulfill the requirement of outputting the required electric power for continuous cruising by the fuel cell".

Paragraph [0037] of the patent specification recites indeed that "a lower limit value and an upper limit value of the output ratio between the fuel cell 40 and the battery 20 are set based on a predetermined reference representative of the vehicle driving conditions."

According to paragraph [0037], it is calculated that a vehicle weighing 2000kg with a motor efficiency of 80% cruising at 120km/h on a gradient of 4.5% requires approximately 65kW, whereby if the maximum required electric power is assumed to be 100kW, the lower limit of the ratio should be 0.65. Hence the board agrees with the appellant that the lower limit of the claimed range is influenced by, among other criteria, both the driving conditions and the vehicle type.

Furthermore this passage can also be interpreted as defining a power minimum for a fuel cell independently of the fuel efficiency, the battery or a proportion of fuel cell power to battery power.

According to paragraph [0038] of the published patent the upper limit of the output ratio may be determined based on a regeneration capacity of the battery, whereby "For example, the maximum regenerative electric power during deceleration is calculated to be 20kW when driving a so-called 10-15 mode with a vehicle weight of 2000kg and a motor efficiency of 80%", and "If the maximum required electric power is assumed to be 100kW, the capacity of the battery 20 required for charging this regenerative electric power is 20kW. Accordingly the upper limit value of the output is set to 0.8."

The upper limit of the ratio is therefore also set taking account of both the driving conditions and the vehicle type, whereby the fuel efficiency does not appear to play any role.

Furthermore, according to paragraph [0041] and figure 5, the fuel efficiency can also be assessed dependent on driving modes referred as 10-15 mode (Japan) or L4A mode (which corresponds to the US FTP-72 mode).

Finally in paragraph [0041] the fuel efficiency is said to become significantly higher in an output range of 40% to 80%. This indicates that the value 0.65 is based on different assumptions and requirements.

The subject-matter of claim 1 is not limited to any particular vehicle type or particular driving conditions, and the appellant has not demonstrated that fuel efficiency was improved with the claimed ratio in any circumstances, so that the claimed ratio appears to be an arbitrary selection, in which no purpose behind the selection can be seen. The third criterion defined above is therefore not fulfilled, so that the subject-matter of claim 1 of the main request lacks novelty having regard to E1 (Article 54 EPC).

3. First auxiliary request

[...]

8. The subject-matter of claim 1 of the main and first auxiliary requests being not novel and the other requests from the respondent not having been admitted into the proceedings, the board has to grant the request of the appellant to set aside the contested decision and revoke the patent.

Order

For these reasons it is decided that:

1. The decision under appeal is set aside.

2. The patent is revoked.

3. The request for referral to the Enlarged Board of Appeal is refused.

This decision T 66/12 (pdf) has European Case Law Identifier:  ECLI:EP:BA:2016:T006612.20161109. The file wrapper can be found here. Illustration "Ecological car" by xedos4 is obtained via FreeDigitalPhotos.net (no changes made).