Acquisitions of nascent competitors by digital gatekeepers are often not covered by EU (or sometimes national) merger laws because they fall below the thresholds that trigger a duty to notify, hence there is a merger gap. After outlining the competition concerns and the legislative activities undertaken or planned by some Member States, we study how such mergers may be reviewed at EU level with a one-stop-shop approach. We show the weaknesses in the Commission’s suggested approach of stimulating more referrals under Article 22 of the EU Merger Regulation and suggest three legislative options to close the merger gap. The paper explores whether Article 114 TFEU may be an appropriate legal basis for such legislative options.