6.6.7 Experiments

The requirement of sufficient disclosure is intended to ensure that the skilled person can carry out the invention without having to do their own research or performing an unreasonable number of experiments. It is not met if they still cannot successfully carry it out after a few instructive attempts and, instead, must first employ their own inventiveness (T 312/88, point 3.3 of the Reasons; T 516/99, point 3 of the Reasons).

The legislative purpose of Art. 83 EPC is to ensure that the skilled person can reproduce the invention without his own research or undue experimentation. Experiments are an undue burden if their primary aim is to find the solution to the problem but not if they are carried out merely to determine the numerical limits of a functionally defined range (T 312/88). They should quickly give a reliable picture of how the products can be produced or manufactured (T 475/88). However, it is not necessary for the experimental data filed with the patent in suit to be an exact repetition of the worked examples of the patent, as long as the experimental work can be regarded as being within the scope of the invention (T 674/96).

For experiments to be considered reasonable, the application need not disclose the best and easiest method; a long and complicated route which is nevertheless clearly successful may be considered reasonable (T 412/93).

The board in T 1133/08, faced with a multitude of options for selecting suitable materials, dimensions and procedural parameters which were merely outlined in the part of description relating to embodiments, found that there was no specific information describing in detail at least one way of carrying out the invention claimed. Experiments were needed to solve the problem (i.e. identify parameters and conditions resulting in a sinusoidal profile), and, as established in T 312/88 in conjunction with T 68/85 and T 18/89, such experimentation had to be considered unduly burdensome. If an invention had several variants, it was very important first of all to describe as many as possible in detail, rather than merely outlining them, to show the skilled person that the invention could be carried out in practice across the entire breadth of the claims. Here, not one single way of carrying out the invention was apparent, nor had any subsequently been demonstrated, e.g. on the basis of experiments. The board also analysed T 14/83, contrasting it with T 412/93 (genetic engineering).

In T 345/09 (method for manufacturing parts with very high mechanical properties) the board found that the skilled person, faced with a lack of relevant examples relating to the invention's essential mechanical features, would have had to carry out a number of tests in order to arrive at it. Given the number of mechanical features (at least eight) and parameters (fourteen), combined with the ranges to be applied to these parameters and the repetitions of tests – needed for some mechanical features having to be guaranteed before and after quenching – all of which were essential to carry out the invention, the research programme facing the skilled person was, the board concluded, so extensive that it amounted to an undue burden.