Just this past Wednesday, the European Court of Justice handed down a judgement in the case C-13/20 Top System on the right to decompilation by a purchaser of software to fix errors, which was discussed here previously in the context of the right to repair.
The court affirmed the right to decompile a program under Art. 5(1) of Directive 91/250/EEC on the legal protection of computer program to fix errors in the operation of the program and that this can include disabling functions of the program. Such a purchaser is not required to satisfy the conditions of Art. 6 of the directive which are concerned with interoperability, for example in competing products according to the court, as was hypothesized in the original article here, however also restricts the allowed decompilation to only fixing the problematic errors. A caveat – as the court points out, Directive 91/250 was replaced by Directive 2009/24/EC but due to the specifics of the case such as the time when the facts took place, the older Directive was applied.
In its 1st question the referring court asked in essence
“whether Article 5(1) of Directive 91/250 must be interpreted as meaning that the lawful purchaser of a computer program is entitled to decompile all or part of that program in order to correct errors affecting the operation of that program, including where the correction consists in disabling a function that is affecting the proper operation of the application of which the program forms a part.”
According to the findings of the court, while decompilation is not mentioned expressly in Art. 5 of the Directive, the acts of Art. 4 such as reproduction and alteration make up decompilation, and according to the court this is also supported by the travaux préparatoires. The most important finding of the court on this first questions is the clear delineation of Art. 5 and 6 of the Directive, with Art. 6 being applicable to interoperability independent of Art. 5, and thus Art. 6 is not a restriction on Art. 5 but stands on its own.
For the second question, the court summarizes this as
“whether Article 5(1) of Directive 91/250 must be interpreted as meaning that the lawful purchaser of a computer program who wishes to decompile that program in order to correct errors affecting its operation must satisfy the requirements laid down in Article 6 of that directive or other requirements”.
This distinction between Art. 5 and 6 is confirmed even more explicitly in the answer to the second question, although the court had already given part of its answer in the answer to the first question. The court then reaffirms that certain conditions are attached to the possibility of correcting errors – such that the resulting code may only be used for correcting errors, may not be distributed and decompilation is not allowed when source code is available, and as far as possible, contractual provisions should be adhered to. Here the ‘as far as possible’ is the important part, as the court reads Art. 5(1) in conjunction with recital 18 to mean that the rightsholder cannot preclude this decompilation by contractual clauses in order to fix errors. This distinction between the articles 5 and 6 in addition to the finding that while contractual provisions should be observed as far as possible, they cannot preclude decompilation to fix errors is really the main gist of the judgement and provides increased legal certainty to companies finding themselves in a similar predicament to the defendant.