The economic downturn caused by the coronavirus pandemics is expected to result in the increased participation of the state in the functioning of markets. One of the forms of this participation is the recapitalization and state shareholding in commercial enterprises, which could lead to anti-competitive effects to the detriment of competitors and consumers. In this regard, the effective enforcement of merger control rules at the EU and national levels gains in importance. The present paper questions the adequacy of the available merger control standards and assessment tools for taking into account potential anti-competitive effects stemming from ownership and non ownership forms of state control over undertakings. The analysis is focused on the experiences of Polish state owned enterprises under the EU and national merger control assessment. It was prompted by the notification of the PKN Orlen/Lotos merger that received conditional clearance from the EU Commission.