Subcontracting and Liability: Qualified Diligence According to the Supreme Court (Judgment No. 14870/2025)

The sector of contracting and subcontracting is constantly at the center of important jurisprudential interpretations. Judgment No. 14870 of June 3, 2025, by the Court of Cassation, provides essential clarification on the nature of the subcontracting agreement and the diligence required of the subcontractor, with significant implications in terms of liability. This ruling is crucial for all operators in the sector, outlining fundamental aspects for risk management and the allocation of burdens.

The Subcontracting Agreement and the Standard of Professional Diligence

Subcontracting is a "derivative" contract, where the main contractor engages a third party to perform part of the work or service undertaken. This dynamic raises questions about the applicable regulations and the level of diligence. Article 1176, paragraph 2, of the Civil Code mandates "qualified diligence" for professional activities. The Court of Cassation, with the judgment under review, reiterates that, unless otherwise agreed, the same regulations governing the main contract apply to the relationships between the contractor and the subcontractor.

The Supreme Court's Ruling: Non-Exclusive Liability of the Subcontractor

The Supreme Court addresses the issue of the scope of qualified diligence, clarifying that there is no inherently different diligence standard for the subcontractor compared to the main contractor. The ruling is clear:

With the subcontracting agreement, which is of a derivative nature, the contractor engages the subcontractor to perform, in whole or in part, the work or service that the contractor itself has undertaken. Therefore, the same regulations governing the main contract generally apply to their relationship, and consequently, both are required to exercise the same qualified diligence pursuant to Article 1176, paragraph 2, of the Civil Code, unless the contractual agreement specifically regulates the relationship by imposing specific and additional obligations on one party compared to the other. (In this case, the Supreme Court quashed the appealed judgment which had affirmed the exclusive liability of the subcontractor for the costs related to the rework of a series of works, without first ascertaining the reasons why the subcontractor should have borne the full burden, thus disregarding the first-instance ruling which had established the joint liability of the sub-contractor and the subcontractor in relation to the activities performed by each).

This ruling is crucial. The Court of Cassation quashed the judgment of the Court of Appeal of Bolzano (April 20, 2019), which had attributed exclusive liability to the subcontractor S. for the costs of rework. The Supreme Court deemed this decision erroneous, as it had not ascertained the reasons for the subcontractor to bear the full burden. The principle is reaffirmed that, unless otherwise contractually agreed, the contractor and the subcontractor are subject to the same qualified diligence (Article 1176, paragraph 2, of the Civil Code). The first-instance ruling, which had recognized joint liability between the sub-contractor and the subcontractor, was implicitly upheld. This means that liability for defects or flaws is not automatically transferred solely to the subcontractor but must be assessed considering the role and obligations of each party, also in light of Articles 1656, 1667, and 1668 of the Civil Code.

Practical Implications for Contractors and Subcontractors

Judgment No. 14870/2025 reaffirms a principle of contractual balance. The practical implications are clear:

• Contractors (Sub-contractors): Do not assume the subcontractor's exclusive liability. Supervise the work and clearly define responsibilities.
• Subcontractors: Are not held to higher diligence standards than the main contractor, unless otherwise agreed. Nevertheless, they must operate with qualified diligence.
• Both: Clarity in contractual regulation is crucial. Specific and additional obligations must be explicitly provided for in the subcontracting agreement to modify the general rule of equal diligence.

Conclusions

The ruling by the Court of Cassation No. 14870 of 2025 consolidates the principle that qualified diligence pursuant to Article 1176, paragraph 2, of the Civil Code applies equally to both contracting parties, the contractor and the subcontractor, unless specific agreements are made. This orientation promotes greater fairness in the allocation of responsibilities and more precise contracts. To prevent disputes and operate with certainty in the complex landscape of contracting, expert legal advice is always recommended for drafting and analyzing subcontracting agreements, ensuring that obligations and expectations are defined with the utmost clarity.