Regulatory change and trading & clearing rulebooks in the EU and UK: What changes in 2026–2027

2026 sees a significant volume of regulatory change moving through both the EU and UK - across trading venues, clearing houses, market structure and digital assets that will continue into 2027 and beyond. While many initiatives share similar objectives - competitiveness, integration, efficiency - they differ in design and execution.

The European Commission has identified competitiveness and cost of capital as a critical challenge for the European Union, noting that “EU capital markets will not succeed in their current structure and require reform.”

In response, the EU Markets Integration Package (MIP), published on 4 December 2025, sets out an ambitious plan to deliver a more integrated European market infrastructure.

The scale of the package is significant: 283 changes across 14 regulations, a further 89 changes across three directives, and the introduction of a new Settlement Finality Directive and Regulation. It is both wide-ranging and complex.

While these proposals are still moving through the legislative process - and further amendment is likely - it would be a mistake to ignore them. Although many of the changes are framed as impacting market infrastructures rather than investment firms directly, their downstream effects could materially reshape trading, clearing, and settlement outcomes over the coming years.

What the proposals aim to deliver

At a high level, the Markets Integration Package focuses on:

• Direct supervision of trading venues (TVs) and central counterparties (CCPs)

• Streamlining market access and infrastructure rules

• Further harmonisation of trading venue rules, including the creation of a pan-European market operator

• Increased competition in settlement

On the surface, these may appear bureaucratic or even uncontroversial in the context of building deeper and more liquid capital markets. In reality, the complexity lies in the interaction of national interests, supervisory models, and commercial incentives.

Key questions remain unresolved:

• How will national priorities shape the proposed pan-European market operators?

• Will expanded ESMA supervision genuinely reduce compliance costs and friction?

• How will exchange groups adapt to a changing competitive and operating environment?

Beyond the headline reforms

Not all relevant developments sit neatly within the MIP itself. For example, there is renewed discussion around bringing exchange-traded derivatives (ETDs) back into the scope of Open Access following their removal in 2020. The Commission’s supporting study strongly endorses open and interoperable clearing and settlement infrastructures.

The package also builds on changes to the consolidated tape for equities. While the current model focuses on EBBO, the MIP would extend this to five levels of market depth and broaden the range of instruments covered. Given that exchanges have won the tender to operate the tape, this is another area where competitive dynamics will need to be inferred from regulatory intent rather than explicit rule text.

Exchange rulebook impact

From a rulebook perspective, the implications are substantial. Changes to supervision structures or the launch of a pan-European market operator will almost certainly require significant restructuring of exchange rulebooks, including the movement and reclassification of existing provisions - even before any functional changes, such as clearing interoperability, are implemented.

The new Settlement Finality Regulation is particularly notable. It explicitly recognises distributed ledger technology (DLT) across the Union and is the only document in the package issued with an official French translation - a signal of both its importance and complexity.

Near-term regulatory change continues

Alongside the MIP, firms are already grappling with a heavy pipeline of nearer-term regulatory change:

• EMIR 3.0 introduces active account reporting and non-EU exposure reporting from summer 2026, requiring firms to maintain backlog data dating back to June 25, 2025. Despite policy intent, liquidity remains concentrated at LCH London, raising questions about whether ESMA’s definition of “representative volume” will evolve.

• The MiFIR Review is now in its implementation phase, with simplified derivatives transparency due from March 2027, alongside unresolved market structure questions such as single volume caps, the PFOF ban (June 2026), clearer SI definitions, and outstanding administrative issues like ToTV.

• In the UK, the Wholesale Markets Review continues to reshape the regulatory landscape. FCA PS25/1 transfers responsibility for commodity position limits from the FCA to venues themselves, triggering changes across both the FCA Handbook and exchange rulebooks.

These developments illustrate how primary legislation increasingly feeds directly into venue rulebooks and firm-level compliance obligations.

Structural change, operational risk

The pace and breadth of reform create a tangible operational risk, particularly for venue members. Missing or misinterpreting a rulebook change can have immediate trading consequences, while evidencing historical compliance becomes harder as complexity grows.

In equities, initiatives such as POATRS and PISCES aim to improve access to growth capital, while the UK simultaneously moves toward T+1 settlement, consults on direct-to-fund models, and expands the Digital Securities Sandbox. Removing layers of intermediation will inevitably force rulebooks to evolve around order routing, best execution, and suitability.

Diverging philosophies, shared complexity

The EU and UK are taking different regulatory approaches. The UK has focused on simplifying the statute book, granting long-term equivalence to EU clearing houses, and moving faster on the consolidated tape. The EU, by contrast, continues to amend and expand regulatory frameworks.

The result is a shift in complexity downstream. While market access may improve, venues and market participants must now interpret, implement, and evidence compliance with increasingly dynamic rulebooks.

Digital assets highlight this divergence. The UK’s Digital Securities Sandbox adopts a modification-based approach, while the EU relies on waivers under the DLT Pilot Regime. As definitions evolve, the impact on venue and clearing house rulebooks remains open-ended.

And that, perhaps, is a topic for another post.