Abstract
The paper contains a legal analysis of certain rules on documenting the performance of conditions, confirming that significant changes appeared upon amending the PPL. The approach to evidence submitted by contractors in proceedings is currently redefined in the case law of the National Chamber of Appeals, but a uniform opinion is still missing on the scope of admissible supplements, new grounds for exclusion due to misleading, as well as in the context of the validity of documents. This demonstrates the need for a comprehensive analysis of this issue, as well as a clear interpretation of the regulations, reflecting the legislator’s objectives.