The subject of this gloss is the responsibility of the autonomous possessor for the collapse of a building or detachment of its parts. Having analysed the judgment, the author observes that the concepts of a structure (building) as well as detachment of its parts are interpreted too broadly in judicial decisions. Not every detachment (such as a destroyed fence and broken glass in the front door or in the balcony balustrade) justifies the strict liability of their autonomous possessor. Therefore, the current position in this respect needs revising. However, in many actual situations, the actions or omissions of other people, including the aggrieved party, may be included in the chain of causation. Consequently, the question arises whether and to what extent these circumstances may affect the autonomous possessor‘s liability and its scope. It is particularly important to determine the aggrieved party’s behaviour which can be qualified as contributing to or increasing the extent of the damage. The extreme positions of individual courts in this respect vary from the necessity of complicity (culpa concurens) to the sufficient requirement of complicity (causa concurens), which causes great uncertainty of decisions that may differ under similar circumstances. The above question as well as other issues regarding the co-responsibility of the autonomous possessor of the structure and other people whose actions or omissions resulted in the damage, have been considered in the gloss to the judgment of the Court of Appeal in Łódź of 11 August, 2021 (I ACa 139/20).