Category: data processing

Designing a wiring path/YAZAKI – T 1371/16 – 17 September 2021

In this decision the subject matter is a simulation for designing a wiring path. Claim 1 does not specify any further use of an output wiring path data of the simulation, further properties or specific data format that could limit the possible uses of the data. Therefore, the output data does not contribute to an “implied” technical effect that is to be taken into account in the assessment of inventive step. Furthermore, the distinguishing features do not include any inventive details of the computer implementation.

Object of the Invention:

  • the application concerns an apparatus and method for aiding a design of wiring paths of wire harnesses in a three-dimensional space such as a vehicle body
  • the design takes into consideration three-dimensional data of a body in which the wire harness is installed, a minimum bending radius of the wire harness which varies depending on a type and the number of wires to be bundled into a wire harness, and a type of the covering of the wire harness
  • Claim 1 differs from the closest prior art in that
    • a storing unit also stores a second minimum bending radius based on force of the worker’s hand
    • a selecting unit selects the largest of the first and second minimum radii if they differ

Board I (inventive step – general considerations):

  • Claim 1 concerns an apparatus for computer aided design of a wire harness wiring path which outputs “data on corrected wiring path” as a final result
  • it thus relates to a design process which uses computer-implemented simulation to produce numerical data describing a wiring path
  • the distinguishing features result in wiring path data being output by the apparatus which take into account the force of the worker’s hand
  • the claimed subject-matter is thus analogous to a computer-implemented simulation of a technical system
  • its patentability is to be assessed taking into account the criteria established by the recent decision G 1/19
  • according to decision G 1/19, if a claimed process results in a set of numerical values, it depends on the further use of such data (which use can happen as a result of human intervention or automatically within a fwider technical process) whether a resulting technical effect can be considered in the inventive step assessment
  • if such further use is not, at least implicitly, specified in the claim, it will be disregarded for this purpose
  • calculated numerical data reflecting the physical behaviour of a system modelled in a computer usually cannot establish the technical character of an invention even if the calculated behaviour adequately reflects the behaviour of a real system underlying the simulation
  • only in exceptional cases may such calculated effects be considered implied technical effects (for example, if the potential use of such data is limited to technical purposes)
  • G 1/19 presents its conclusions for the application of the COMVIK approach to simulations
  • it explains that the underlying models of the simulation may contribute to technicality if, for example, they form the basis for a further technical use of the outcomes of the simulation (e.g. a use having an impact on physical reality)
  • in order to avoid patent protection being granted to non-patentable subject-matter, such further use has to be at least implicitly specified in the claim
  • G 1/19 provides some examples of further technical uses of the numerical data resulting from a simulation, which under certain conditions may be potential uses, implicitly specified or implied by the claim
  • one example is the use of the data in a manufacturing step, which “would of course be an argument in favour of patentability”
  • another example of a further technical use is the use of the data in controlling a technical device, which can be recognised if the resulting numerical data is specifically adapted for “the purposes of its intended technical use“, i.e. for controlling a technical device
  • in that case, the data is considered to have a technical character because it has the potential to cause technical effects
  • either the technical effect that would result from the intended use of the data could be considered “implied” by the claim, or
  • the intended use of the data (i.e. the use in connection with a technical device) could be considered to extend across substantially the whole scope of the claimed data processing method
  • these arguments cannot be made if claimed data or data resulting from a claimed process has relevant uses other than the use with a technical device

Board II (inventive step):

  • in support of inventive step, the appellant argued that the distinguishing features achieved a technical benefit over D1 by providing a wiring harness design capable of being installed simply and effectively in circumstances where a design output by the system of D1 would not
  • by providing the second minimum radius based on the force achievable using an assembler’s hand, the invention was “able to generate the design of a wiring harness which is easier to manufacture, yet which also does not have excessive stress generated on it, and yet which is also of as short a distance as possible in order to reduce cost and weight, as well as potentially improve the reliability of the systems utilising that harness through shorter communications paths“
  • the distinguishing features ensured the manufacturability of the design

Appellant I (inventive step):

  • according G 1/19 the claimed invention produced data that allowed manufacturing the wire harness
  • the numerical data produced by the claimed apparatus reflected the physical structure of the designed wiring path and not merely the physical behaviour of a simulated system
  • the claim specified at least implicitly a further use of the designed wire harness which had an impact on physical reality, and therefore fulfilled the requirements expressed in G 1/19
  • as with a claim to a bicycle that did not need to specify that the bicycle had two wheels, there had to be a limit to which features had to be specified in the claim for recognising the technical purpose
  • the claim explicitly specified that the design aiding apparatus comprised a designing unit and that the wiring harness was installed in a vehicle body
  • it was sufficient to show that the end result had, at least implicitly, a technical purpose
  • it was clear from the claim that the technical area of the invention was the installation of the wiring harness along the path

Board III (inventive step):

  • the board is however not convinced that the distinguishing features contribute to a technical effect in accordance with the criteria established by decision G 1/19
  • the only purpose of the wire harness wiring path design aiding apparatus according to claim 1 is to output “data on corrected wiring path data”, which is numerical data about the wiring path design
  • as explained above, the distinguishing features result in wiring path data being output by the apparatus which takes into account the force of the worker’s hand
  • claim 1 does not specify any further use of the output wiring path data, further properties or specific data format that could limit the possible uses of the data
  • in view of that, other relevant uses of the output data for non-technical purposes, for example informational, study or training purposes, are within the scope of the claim
  • since the data can be output in any form or format, it cannot be considered to be specifically adapted for the purposes of an intended technical use
  • in particular, the output data is not specifically adapted to be used in controlling a technical device or manufacturing a wiring path
  • it can thus be concluded that the data produced by the apparatus of claim 1 is not limited to a further technical purpose and does not contribute to an “implied“ technical effect that is to be taken into account in the assessment
  • furthermore, the distinguishing features do not include any inventive details of the computer implementation, and the appellant has not argued otherwise
  • –> no inventive step

Masking a private key/CERTICOM – T 0556/ 14 – 28 July 2016

In this decision in a patent a method of masking a privat key is claimed. It is considered not to be a mathematical method as such, because storing on a smartcard (hardware) was claimed. The claimed method achieves some protection against power analysis attacks and thus have a technical effect. An inventive step is acknowledged if, having regard to the state of the art, the invention is not obvious to a person skilled in the art. It is not necessary that the invention is a technical improvement over the prior art. The claimed method is an alternative approach compared to the closest prior art and is not suggested.

Object of the Invention:

  • the invention relates to a method for masking a private key used in cryptographic operations on a security token such as a smartcard against power analysis attacks
  • the security of cryptographic systems relies on a particular piece of information being kept secret, and power analysis attacks try to extract information about the secret by statistically analysing the power consumption of the security token when carrying out the cryptographic operation
  • the attacker of the power analysis attack considers the security token “to be a black box which contains a known algorithm and an unknown key” and in order to obtain the required statistical information, repeatedly executes the algorithm with varying parameters under his control
  • masking is, roughly speaking, a technique of randomising the calculations carried out in each instance of the cryptographic algorithms, so that their result remains the same but no relevant statistical information about the key can be gathered by repeated execution
  • first a private key d, which in elliptic curve cryptography is multiplied with a point P to derive a public key Q = dP, is “divided” into a plurality of parts
  • specifically disclosed is a division into two parts b1 and b2 such that d = b1 + b2
  • then a random number π is generated and the values of the parts are updated as b1 = b1 + π mod n and b2 = b2 – π mod n, where n is the number of points on the elliptic curve used
  • the cryptographic operation, in which the private key is “used”, is then carried out by “utilizing” the individual and modified “new parts”

Board I (Art. 52 (2) and (3) EPC):

  • due to the express reference in claim 1 to a smart card on which the key parts and also the new parts are stored, the claimed method of masking is not a mathematical method as such (Claim 1: A method […] storing the new parts on the smart card […])
  • due to the reference to the smart card and in view of the description the skilled person would understand the claimed masking operation to be an automated one to be carried out on the smart card

Board II (technical effect of masking)

  • central to any masking method is the modification of a mathematical method in such a way that its repeated execution is less prone to a statistical analysis revealing the properties of a secret
  • since the result of the computation must not change, this means that masking, in essence, relies on replacing one mathematical method by another which has an equivalent result
  • however, the modified computation is meant to be better protected against power analysis (or other sidechannel) attacks when carried out on hardware
  • as such, the idea of masking is well-established in the art as a protection against such attacks
  • the board accepts as a technical problem the protection of a cryptographic computation against power analysis attacks – if, and only if, the computation is actually carried out on hardware and thus open to such attacks
  • claim 1 specifies a masking method carried out on hardware
  • even though claim 1 literally specifies only the storage of the key parts on a smart card, in the board’s view the skilled person can only understand the method of claim 1 as a fully computer-implemented method
  • the claimed randomisation steps, namely the calculation of two randomised key parts and the computation of Q = b1P + b2P instead of Q = dP, does achieve some protection against power analysis attacks and thus have a technical effect
  • à mathematical steps contribute to the technical character of claim 1

Board III (inventive step)

  • the differences between the claimed matter and D2 (closest prior art) are
    • that D2 relates to RSA (Rivest-Shamir-Adleman = public-key cryptosystem) whereas claim 1 relates to elliptic curve cryptography (ECC), and
    • the masking of the secret by randomised splitting
  • the problem solved by the invention over D2 can therefore be considered as adapting the masking method of D2 to other cryptographic operations particular side channel attacks

Respondent I (inventive step)

  • the randomised splitting steps do not make the claimed method more efficient than the one according to D2
  • on the contrary, in fact: while the method of D2 masks the given calculation by the addition of one multiplication and one addition, the claimed method would be adding two multiplications and one addition and thus be less efficient

Board IV (inventive step)

  • the disadvantage of a method may be outweighed by an advantage it may also have
  • for instance, a slower method might have a statistically significant protective advantage against particular side channel attacks
  • the board hastens to add that the patent contains no detail whatsoever that might allow a judgement or even a sophisticated guess as to the relative security of the proposed measure against any particular power analysis attack
  • however, the board considers that the comparison between the claimed method and that of D2 cannot be reduced to the number of additions and multiplications
  • inventive step is acknowledged if, having regard to the state of the art, the invention is not obvious to a person skilled in the art
  • it is not necessary that the invention is a technical improvement over the prior art
  • the claimed randomized splitting and the adding of an “effective zero” according to D2 are alternative approaches and that the change from the latter to the former is not suggested by the change from ECC to RSA
  • the respondent has also not put forward any fundamental mathematical considerations which would, to the board’s satisfaction, suggest this change
  • the respondent was not able to convince the board that the skilled person starting from D2 would be led, in an obvious way, to the randomized split according to the invention
  • –> the claimed method shows the required inventive step over D2

Conclusion:

There are all necessary elements which are necessary that the mathematical method is considered for inventive step at the EPO:

  • a mathematical method
  • a use: computer implementation of the mathematical method on a smartcard
  • the use is technical: because it contributes to a technical effect, namely the protection of a cryptographic computation against power analysis attacks – if, and only if, the computation is actually carried out on hardware and thus open to such attacks

Koprozessor zur modularen Inversion/GIESECKE & DEVRIENT – T 2318/08 – 23. Mai 2012

This decision provides a known cryptographic coprocessor and a known Euclidean method. However, it is not known how to use free bit sections in the coprocessor to speed up the method. Therefore, the clever use of a known coprocessor to speed up the implementation of an equally known method solves a technical problem.

Object of the Invention:

  • the invention relates to a method for calculating the modular inverse of a value u to a modulus v, which is relevant in cryptographic methods
  • the invention is based on a known extended Euclidean method for calculating the modular inverse
  • the core idea of the method is not to represent the output values u and v “right-aligned” in the low-order bit positions as usual, but to shift them to higher-order positions to such an extent that space is created in the low-order positions for the other parameters of the method
  • only the calculation steps of the standard Euclidean method need to be carried out on the modified representation in order to obtain the results of the extended method
  • the new method therefore requires fewer calculation steps than the extended Euclidean method, but at the cost of a longer bit length for the input values
  • the practical relevance of the method results from the following observations:
    • in cryptographic practice, modular inversion is typically performed with a coprocessor designed for operations on integers, whose bit length in turn depends on the usual key length in RSA (= Rivest-Shamir-Adleman = public-key cryptosystem)
    • the so-called EC methods (= Elliptic Curve), which are an alternative to RSA, use significantly shorter keys so that modular inversion only has to be carried out for smaller numbers
    • accordingly, if a coprocessor optimised for RSA is used for EC, a part of its bit system remains unused
    • the method according to the invention utilises these already existing surplus bits to accelerate the desired method

Board:

  • the skilful use of a known coprocessor to accelerate the implementation of an equally known method solves a technical problem and can therefore in principle fulfil the requirements of Article 56 EPC
  • the examining division based its rejection on the fact that the subject-matter of independent claim 1 could not, according to its wording at the time, be said to provide a solution to this technical problem
  • to this end, it lacked, on the one hand, the limitation to a coprocessor “intended for integer calculations with at least the increased bit length” and, on the other hand, the indication that the auxiliary variables were carried in the low-order bits of the increased bit length
  • the present claim 1 is now limited as claimed:
    • the claimed coprocessor is “provided” for a bit length greater than that required for the input values u and v
    • according to the claim, the surplus bits are utilised by shifting u and v into higher “bit sections” by multiplication by an expansion factor, and introducing “disturbances” into the low-order bit sections thus freed up, which serve as output values for auxiliary variables of the subsequent calculation
  • from the fact that, on the one hand, cryptographic coprocessors and, on the other hand, the Euclidean method and its variants are known, it only follows that the implementation of Euclidean methods on cryptographic coprocessors would be obvious to the skilled person
  • however, this does not indicate that free bit sections in such a coprocessor can be used in the claimed manner to accelerate the method
  • –> inventive

Classification method/COMPTEL – T 1784/06 – 21 September 2012

In this decision, the appellant criticises the COMVIK approach on several points. The Board disagrees. With regard to inventive step, according to the Board, there is a lack of “technical purpose” according to T1227/05.

Information from the author: “technical purpose” is no longer sufficient according to decision G1/19 for non-technical features to make a technical contribution. According to current case law (as of August 2024), in such a case a further or intended or implied technical use is required.

Object of the Invention:

  • data records, e. g. the duration and data volume of a telecommunication connection, that are sorted into service classes, in particular for rating and billing purposes
  • identifying the class of a service from a data record forms a performance bottleneck once the number of services is increased to the thousands
  • the application seeks to provide a method which can handle large numbers of service classes more efficiently than the conventional use of conditional statements does
  • the solution is based on reducing, as a first step, a large number of service classes into specific sets
  • these sets are then intersected in a final step
  • this algorithm classifies data records more efficiently

Board (COMVIK approach):

  • it would appear paradoxical to the Board to recognise an inventive step on the basis of a non-technical innovation (such as an organisational, administrative, commercial or mathematical algorithm) having no technical implication other than the (obvious) desire for its implementation on a general-purpose computer

Appellant I (COMVIK approach):

  • claimed subject-matter as a whole should be examined for the presence of an inventive step once the subject-matter as a whole has been found to meet the technology criterion of Article 52(1)(2)(3) EPC
  • Article 56 EPC 1973 should be applied independently of Article 52(1)(2)(3) EPC because Article 52(2) EPC has to be applied independently of Article 56 EPC 1973

Board I (COMVIK approach):

  • the Board does not accept such formal reasoning and points out that it is normal and often necessary for legal provisions to be in an asymmetric relationship or hierarchical dependency
  • for example, the novelty of a claim has to be examined independently of inventive step considerations, whereas a finding of inventiveness presupposes a novelty examination
  • another example is the validity of a priority claim which has to be checked independently of novelty and inventive step requirements, whereas novelty and inventive step cannot be established independently of the validity of a priority right.

Appellant II (COMVIK approach):

  • regarding the Board’s insistence on a technical problem when applying the problem-and-solution approach, the appellant disputes that such a requirement can be deduced from the EPC or introduced from its Implementing Regulations
  • the appellant refers inter alia to decision T 473/08 (by a different Board) to point out that “a non-technical problem can have a technical solution“

Board II (COMVIK approach):

  • there is no divergence, the Board agrees to the statement that a non-technical problem can have a technical solution
  • on the other hand, where an intrinsically non-technical solution (mathematical algorithm) seeks to derive a technical character from the problem solved, the problem must be technical
  • this is the point on which the present case hinges

Appellant III (COMVIK approach):

  • another argument of the appellant refers to the legislative history of the EPC (travaux préparatoires) which is said not to provide any explicit support for a cumulative application of Article 52(2) EPC and Article 56 EPC 1973

Board III (COMVIK approach):

  • the restriction of substantive patent law to technical subject-matter is so self-evident that the founding fathers of the EPC did not even mention that requirement in the original (1973) version of Article 52(1)
  • the explicit clause “in all fields of technology” was not added to Article 52(1) until the Diplomatic Conference in the year 2000 harmonised the Article with the TRIPs treaty
  • nevertheless, Article 52(1) EPC has always been understood as referring to technical inventions

Board IV (inventive step):

  • as the algorithm is a mathematical (inter alia Boolean) method and mathematical methods as such are deemed to be non-inventions (Article 52(2)(3) EPC), a technical character of the algorithm could be recognised only if it served a technical purpose (T1227/05)
  • however, the automatic classification of data records according to claim 1 serves only the purpose of classifying the data records, without implying any technical use of the classification
  • the claim covers any non-technical (e.g. administrative or commercial) use of the classified data records
  • in the light of the description, the classification method prepares rating and billing procedures
  • the Board does not consider the result of the algorithm — a set of classified data records — as technical

Board V (inventive step):

  • enhanced speed of an algorithm, as compared to other algorithms, is not sufficient to establish a technical character of the algorithm (T 1227/05)
  • if a computer-implemented algorithm runs more quickly, the resulting saving in energy is a technical effect inherent to the normal interaction of software and hardware, i.e. it is not a “further” technical effect of the algorithmic program controlling the computer (T 1173/97)
  • the claimed algorithm may allow a data record to be processed in a parallel computer architecture as the various fields of a data record can be judged separately in a first level of processing
  • however, claim 1 is not limited to an implementation on a parallel hardware structure
  • in fact, the application as a whole is silent on parallel data processing (Parallel processing has been mentioned by the decision under appeal and addressed by the statement setting out the grounds of appeal)
  • –> no inventive step