Three long years of G20 regulatory rewrite pain – and what comes next

September’s Hong Kong Monetary Authority (HKMA) Rewrite go-live felt like the final milestone in three or four years of regulatory reporting rewrites pain. HKMA’s changes were the last big jigsaw piece in a series of G20 rule revisions that started with the CFTC Rewrite way back in December 2022.

For firms active across multiple jurisdictions, this hasn’t been “a bit of change”- it’s been a rolling transformation of how OTC derivatives are reported, validated, reconciled and governed.

In many ways, the last four years of change have mirrored my own journey here at Kaizen. Joining in June 2021 with a remit to lead and expand Kaizen’s North American services we began with the SEC’s Security-Based Swap Reporting (SBSR) implementation. We then pivoted to the first phase of the CFTC’s Rewrite and the changes have been coming thick and fast since then.

The rewrites in fast forward

After years of relative stability, the pace since late 2022 has been relentless and has included:

December 2022 – CFTC Rewrite
A complete overhaul of the US derivatives regime: new data standards, more fields, tougher validations and a much sharper view of what “good” reporting looks like.
December 2022 – SEC SBSR and Canadian CSA alignment
SEC Security-Based Swap Reporting went live in two stages, then was reshaped when the CFTC Rewrite arrived. DTCC was allowed to apply much of the CFTC Rewrite model to Canadian CSA reporting, pulling Canada into roughly the same orbit.
January 2024 – CFTC Phase 2
UPI adoption for everything except commodities, driving more standardisation but more complexity for front-to-back systems and controls.
April 2024 – JFSA Rewrite and EU EMIR Refit
Japan joined the party with its own rewrite, while the EU’s EMIR REFIT changed fields, formats and lifecycle reporting fundamentally.
September 2024- UK EMIR Refit
A separate but related regime for the UK post-Brexit, with its own implementation and quirks.
October 2024 – ASIC and MAS Rewrites
Australia and Singapore implemented their G20-aligned rewrites, each with local flavour.
July 2025 – CSA Rewrite (Round Two)
Canada’s second swing, absorbing lessons from earlier reforms and the CFTC-style approach.
September 2025 – HKMA Rewrite
The “grand finale” of this wave, as Hong Kong landed its own version of the global agenda.

Battered, bruised…and still standing

Most banks and reporting firms are emerging from this period a bit battered, but undeniably wiser.

From Kaizen’s vantage point, we’ve seen clients:

Rebuild reporting architectures to support ISO standards, UPIs and new lifecycle models
Re-map hundreds of fields across multiple regimes under intense time pressure
Strengthen control frameworks – especially reconciliations and completeness/accuracy checks – to cope with far more granular data

It hasn’t always been elegant, but the resilience, dedication and problem-solving across the market has been impressive. If I may be so bold, the industry as a whole should take a moment to give themselves a pat on the shoulder for what has been collectively tackled and accomplished.

The regulatory change calendar over the last few years was nothing short of ridiculous, but we didn’t flinch, and here we are emerging on the other side.

Spoiler alert…this isn’t the end

Tempting as it is to declare victory, the regulatory carousel never really stops. On the G20 reporting side alone, the next wave already includes:

January 2026 – UK EMIR validations
Revised validation rules will tighten expectations on data quality and consistency.
April and September 2026 – EMIR Inter-TR Reconciliation uplift
The Inter-TR Reconciliation scope is due to increase to around 150 fields in April 2026 for the EU and September 2026 for the UK – a significant jump in matching expectations and breaks management.
CFTC: Phase 3 (and maybe 4)
The CFTC still has UPI adoption for Commodities, 49 proposed fields and a delayed move to ISO 20022 XML waiting in the wings. Whether it lands as one or two further phases, we’re not done.
CSA: Derivatives Data Technical Manual v2.0
Somewhat hilariously, Canada managed to issue a 2.0 version of its Derivatives Data Technical Manual two weeks before the 1.0 version went live on 25 July. Most changes are minor, but it points toward another implementation date once consultation feedback is digested.

So no, this is not “the end”. It’s more like the end of one particularly brutal season, with the next one already in rehearsal.

ESMA’s Call for Evidence: Slow and Dangerous

Alongside all of this, ESMA has launched a Call For Evidence (CFE) on reducing reporting burdens across EMIR, MiFIR and SFTR. The goal is to cut duplication and conflicting standards, something most firms would happily see.

Trade associations such as ISDA and ICMA have suggested, among other things:

Limiting ETDs to MiFIR and OTCs to EMIR
ETDs would align with market abuse detection under MiFIR, while OTCs sit with systemic risk monitoring under EMIR – which is where they arguably always belonged.
Single-sided reporting with a clear hierarchy
EMIR is still an outlier with dual-sided reporting and mandatory reconciliation of both sides. A move to single-sided reporting and a clear responsibility hierarchy would remove a lot of operational friction.

Ordinarily, you’d expect ESMA’s CFE to take years to turn into anything concrete. But with US priorities and timelines uncertain – including when the CFTC will tackle its remaining Rewrite elements – ESMA’s slow-and-steady approach may yet deliver the next major structural shift in G20 reporting.

So where are we now?

The first wave of rewrites – CFTC, EMIR, JFSA, ASIC, MAS, CSA, HKMA – is largely through initial implementation
A second wave is forming around enhanced validations, expanded reconciliations and “day 2” fixes
And in the background, structural debates – like ESMA’s CFE – could reshape the landscape again, hopefully with simplification in mind.

The bulk of the reporting rewrites have been delivered. But the regulators will continue to assess the data they are receiving and look at what their counterparts have done. Along with the future changes we currently know about, it’s a safe bet that we can expect some more changes to be announced going forward. The carousel continues to spin.