This paper examines how the proposed Regulation on foreign subsidies distorting the Single Market (the “FSR”) will have a significant impact on M&A transactions by imposing a notification and stand-still obligation with respect to the transactions covered by the FSR. The European Commission shall be the sole authority competent to ensure application of the FSR. It may inter alia order the dissolution of the transaction concerned and/or impose significant fines on the undertakings involved in said transaction. Its decisions may be subject to judicial review by the Union courts, however. The focus of this paper is the interests and ability of competitors to the undertakings involved in the M&A transaction to lodge complaints to the Commission and take subsequent legal action before the Union courts and/or damages actions before the national courts.