The key criteria for the equipment is the intended function that the equipment supports. Software (SW) per se is not always subject to certification but the function the SW supports. If the intended supported function is not subject to certification, then the SW is not required to undergo the certification process. In the example, an ADS-B station will support the SUR function, and thus, as per Article 5 of Regulation (EU) 2023/1768, the equipment (including the associated SW) will be subject to a declaration by a design or production organisation (DPO).
