Merger, she wrote (Part 1): How Brussels rewrites its merger guidelines

The trail to the new Merger Guidelines draft begins outside competition law. Mario Draghi's 2024 report on European competitiveness diagnosed a continent that had stopped scaling, hobbled by short investment cycles, fragmented capital markets and a timid industrial policy. Among its many recommendations was a sharper alignment of competition policy with industrial strategy and strategic autonomy. That recommendation was promptly absorbed into the political guidelines of the second von der Leyen Commission and, more concretely, into Executive Vice-President Ribera's mission letter, which contains a direct instruction to review the Horizontal Merger Guidelines and give adequate weight to resilience, efficiency, innovation, and the changed defense and security environment.

What followed was a translation from political mandate into legal text. The Competitiveness Compass of January 2025 confirmed the review; the Clean Industrial Deal of February 2025 added sustainability and clean innovation to the brief. Two parallel consultations in May 2025, one general consultation and one dealing with seven topic papers, ran from 8 May to 3 September 2025 and drew nearly 200 responses. Those were then synthesized by the Commission into an overview of themes published in October 2025, the backbone of two technical stakeholder workshops that were held on 4 December 2025 and 20 January 2026; a closing conference followed on 5 March 2026, chaired by Competition Commissioner Teresa Ribera.

The final draft is the result of that complex pipeline, meaning that it is, besides its anchoring in existing laws and dedicated stakeholder consultation on the substance of merger control, also a document that was written under explicit political pressure – and the negotiations behind it are visible in places where the prose is unusually careful.

That care is most visible in how the draft handles the question of European champions. Two weeks before publication, an earlier version of the draft was leaked to the Financial Times, which drew the headline that the EU was poised to relax merger rules to create European champions. The day after, Commissioner Ribera told Bloomberg that the project should not be read as "an argument to deregulate, dismantle or reduce safeguards", echoing concerns voiced by five Member States (Finland, Ireland, the Czech Republic, Estonia and Latvia) that had already lodged a joint paper on 23 February 2026 pushing back against any loosening of the EU's merger rulebook.

Interestingly, Ribera's President in the Berlaymont, Commission chief Ursula von der Leyen, had emphasized in parallel that the rules should equip Europe to compete globally while preserving the predictability and legal certainty investors expect. She thereby appeared to embrace the journalistic framing surrounding the leak, signaling that the EU's “tone from the top” pulled in different directions – and that the draft now has to carry all of them.

It seeks to do so by leaning into a new vocabulary of pro-competitive scale without softening the SIEC test and providing new opening pages that read as a manifesto.

EU merger control, the Commission writes, is not only there to police market power. It also supports the EU's broader policy objectives: the competitiveness and resilience of the internal market, the security and diversification of supply chains, the protection of innovation and investment competition, the preservation of green innovation, and even media plurality (para. 9). Mergers that bring "increased scale and consolidation" can be viewed positively (para. 7) – a sentence the HMG simply did not contain. The institution presents itself as both guardian of contestable competition and facilitator of European competitiveness, and the draft frames those as a single mandate.

On the back of this, the draft introduces a category new to any prior merger guidance: scale-enhancing mergers. These are mergers that combine complementary capabilities or activities, particularly across Member States, to enable European firms to reach the size needed to compete globally. The draft sets out three principal channels through which such mergers can contribute to competitiveness: innovation and technological progress; market integration and global reach; and security and resilience, including defense readiness (para. 15). Acquisitions of start-ups, separately, are flagged as unlikely to give rise to competition concerns (para. 16) – a signal whose substance is unpacked in the Innovation Shield and to which part 2 of this series will return.

Notably, and presumably calming Commissioner Ribera's nerves, none of this displaces the SIEC test. The Commission is explicit that the benefits of scale must be distinguished from increases in market power that would harm competitiveness, resilience or consumers (para. 18). The structural change is that scale now sits inside the analytical framework as a new parameter, albeit with the evidentiary burdens that label carries. Put simply: a merger party can now argue scale on the merits, and the Commission has committed to listening – but only within the SIEC envelope. That continuity was confirmed before publication by Guillaume Loriot, the Commission's top merger official, who told a Bruges conference in April that merger control is "an instrument in the symphony orchestra" but not the elixir for Europe's structural ills. Price competition remains the staple of merger review, even as the formal register of parameters widens.

The guiding principles section is where the analytical novelty sits. The Commission's burden – to establish whether a merger overall results in a SIEC – is unchanged (para. 21). What changes is the formalization of the merging parties' counter-burden into something the draft calls a theory of benefit. If the parties consider that their merger gives rise to efficiencies, they must, as part of their prospective analysis, articulate and substantiate a theory of benefit in due time (para. 25). The regime that follows holds the parties to the same standard of proof and the same evidentiary discipline that the Commission applies to its theory-of-harm case, while shifting the burden of articulation onto the parties.

That symmetry has consequences. The Commission states, plainly, that it exercises its margin of discretion according to the same principles with regard to evidence underlying both theories (para. 27), and the merging parties are subject to the same evidentiary standard when establishing the facts in support of their claimed efficiencies (para. 26). Notably, there is no strict hierarchy between qualitative and quantitative evidence (para. 31), and the standard of proof for both sides is more likely than not (para. 32) – a clarification that absorbs the ECJ's CK Telecoms ruling (Case C-376/20 P, 13 July 2023) and is intended to end a long-running debate about whether the Commission applies a heightened standard to its own SIEC findings. Early engagement on efficiencies, including during pre-notification, is now expressly welcomed (para. 36).

That is a procedural invitation practitioners have been waiting for since the old HMG first conceded that efficiencies could matter in principle (with the Commission then too often declining to engage with them in practice), and the new framework already appears operational: two days before the published text appeared, the Commission's clearance of the Airbus/Air France A350 components JV (M.11295) engaged with the parties' efficiency claims in Phase I despite the deal clearing unconditionally – a fact the Commission deliberately stressed in its press release on the case. The case team has not waited for the consultation to close to apply the early-engagement invitation.

That said, the expanded vocabulary of pro-competitive scale is matched by a parallel expansion of harm-side categories, which part 2 of this series will walk through.

Other guiding principles in the draft’s introductory parts are refined rather than reinvented. What stands out is how the parameters of competition are broadened to encompass output, quality, choice, capacity, investment, innovation, privacy, sustainability and resilience, including security of supply (para. 20) – virtually mirroring what the Commission now considers formative for “competitiveness”.

On top of that new complexity, the counterfactual analysis appears more sophisticated than under the 2004 HMG framework. Pre-merger conditions remain the default benchmark, but the draft sets out specific circumstances in which the Commission will adjust that benchmark: (1) for sufficiently certain future market changes unrelated to the merger; (2) for non-representative present conditions due to cyclical shocks, crises, or merger-related effects; and (3) exceptionally, for alternative mergers the parties would have pursued absent the deal (paras. 39-44).

Taking these aspects together raises the question whether the draft offers a net benefit to merger parties in terms of predictability. The old HMG and NHMG were not loved because they were substantively perfect, but they were useful because they were relatively crisp and analytically clean. The new draft is more textured, more contextual and more evidence-intensive. As an instrument for “self-assessment” – that is, merger feasibility considerations – it will be more demanding to operate. For the cleanest deals at one end, and for the most plainly problematic deals at the other, the practical answer will not change much. The middle band, where most of the work actually sits, is where that cost will be felt – a cost that is, on the other hand, the flipside of newfound leeway for many deals that will benefit from the more comprehensive and nuanced analytical framework, which invites pro-merger arguments that would have been challenging to present under the old system.

Last but not least, two further items are worth flagging:

• The failing firm doctrine retains its three cumulative criteria, but now expressly acknowledges failing division claims in exceptional circumstances.
• The draft enshrines the Commission’s strict stance on document submissions and evidence: the merging parties' submissions must be complete, correct and not misleading; the Commission may rely on a single document of undoubted probative value; and the views of customers and competitors are weighed with awareness of those parties' commercial incentives.