Collateral proceedings are characterised by their speed and the related evidentiary limitations, hence, the concentration of evidence is extremely important already at the moment of filing a security application with the Court .
This is more than once experienced by patent holders, who in order to bring about an immediate cessation of infringement of their exclusive right, commission private experts to draw up an opinion, which they then attach to the motion for security as confirmation of the circumstances they have formulated – most often concerning incorporation of patent claims in a third party’s product .
Such practice is also accepted by the Regional Court in Warsaw, which in one of its rulings1 indicated what features a private opinion should have in order to be deemed evidence in a case constituting a substitute for an expert opinion. Only a substitute, because in the main proceedings, the Court should reach for special knowledge when it becomes necessary to clarify such issues, the matter of which exceeds the scope of knowledge arising from the life experience of persons with general education2. Otherwise, the decision issued runs the risk of automatically accepting the legitimacy of the allegation formulated on the basis of Article 278 § 1 CCP.
Thus, a private opinion is recognised as a means of substantiating a fact, the establishment of which requires special knowledge, and this no longer constitutes a major procedural controversy.
However, it should still be borne in mind that in the light of Article 245 of the CCP, a private opinion constitutes only evidence that the person who signed it made the statement contained therein. Therefore, the Regional Court in Warsaw emphasises that:
- it is necessary to analyse the reliability of the preparation of the private opinion and the accuracy of its conclusions when confronted with the material on the basis of which it was prepared ,
as well as that:
- a private opinion may not contain any internal contradictions if factual findings are to be made on its basis as a whole.
The above results in the fact that the assessment of a private opinion may be subject to review on the basis of a plea of violation of the provision of Article 233 § 1 CCP, i.e. exceeding the limits of free assessment of evidence, like any other evidence .
The modern conduct of patent litigation has led to the widespread recognition of private opinions drawn up by qualified experts in specific fields as an alternative to expert opinions, or at least as a temporary alternative pending its proof in the main proceedings on the merits .
Ask author 
Polish