Wednesday, 11 November 2009

T 1514/05 - Explore All Roads that Lead to Rome

[…] The Board considers D12 to be the closest prior art. [3.1.1]

[…] Contrary to the argument of the patentee, the Board does not consider that D12 must not be considered to be the closest prior art on the grounds that this document persuaded the skilled person not to use veneering (placage) for covering the alloy sheet. [3.1.3]

[…] Be that as it may, the Board has to examine of inventive step with respect to the disclosure of D12 because, according to the case law of the Boards of appeal, when the skilled person is faced with several possible (praticable) problem-solution approaches that could render the invention obvious, the nature of the problem-solution approach in itself requires that all the avenues (pistes) be examined before inventive step can be asserted (T 967/97 [I]). [3.1.6]

I find this statement very sound. If this principle was applied more often, the problem-solution approach would be less criticized. I understand that the German jurisdictions reject the problem-solution approach because it limits the evaluation of inventive step to one single starting point, i.e. the document considered to be the “closest prior art”. In reality, claimed subject-matter can be non obvious when starting from the “closest prior art” and obvious when starting from another prior art. This is neglected in the actual EPO practice, where often the decisive battle is concerned with which document is considered to be the closest prior art. Once this choice has been made, the case is lost or won.

I should add that the translation of the headline of T 967/97 provided in T 1514/05 is poor. I would rather translate : “If several paths to the solution (Lösungswege) along which the invention could be obvious offer themselves to the skilled person, then the reasoning (Ratio) underlying the problem-solution approach requires to examine the invention with respect to all of these paths to the solution before a decision confirming the presence of an inventive step can be taken.”

The decision then proceeds with the assessment of inventive step and comes to the conclusion:

If follows from these considerations that the skilled person would arrive at the subject-matter of claim 1 without exercising any inventive skill, by proceeding along three successive steps, each of which is obvious, both in itself and in sequence: (i) selecting of a type of veneering for the protection of the core sheet against corrosion; (ii) choosing a veneering alloy that is compatible with the core sheet and which offers sufficient protection in terms of potential difference; and finally (iii) optimising the anodic protection by reducing the said potential difference by means of a reduction of the Zn content in the veneering alloy.

This conclusion is in conformity with the case law of the Boards of appeal according to which a solution is obvious, even though it may necessitate two or more stages, if the technical problem faced by the skilled person leads him to the solution by stages and if he finds each stage obvious, as far as the result obtained and the residual problem to be resolved are concerned (T 623/97 [4.4]).

This conclusion is coherent with the logic underlying the established case law (cf. T 400/98 [4.4.6]) according to which, when the skilled person has at his disposal several equivalent existing solutions for solving the technical problem, the choice of one of the possible solutions does not require any particular skills and for this reason does not involve an inventive step. Thus the choice of reducing the Zn content so that it varies within the domain of the claimed values is an obvious alternative for the skilled person. [3.3.7]

As far as the stages of a process are concerned, I would have preferred a reasoning based on the concept of “partial problems”. The reasoning of T 623/97 does not explicitly take into account a possible synergy between successive stages, in which case the stages could not be treated separately.

To read the whole decision (in French), click here.