Judgment of the Court (Fifth Chamber) of 27 November 2019.#Tedeschi Srl and Consorzio Stabile Istant Service v C.M. Service Srl and Università degli Studi di Roma La Sapienza.#Request for a preliminary ruling from the Consiglio di Stato.#Reference for a preliminary ruling – Articles 49 and 56 TFEU – Public procurement – Directive 2004/18/EC – Article 25 – Subcontracting – National legislation limiting the possibility of subcontracting to 30% of the total value of the public contract and prohibiting prices for subcontracted works, supplies or services from being reduced by more than 20% compared to the prices stated in the decision awarding the contract.#Case C-402/18.