CSSF declares Circular 21/783 outdated from 23 August 2026
Luxembourg credit institutions, investment firms, CASPs and specialised PFS lose Circular 21/783 as the market-data reference on 23 August 2026 and work directly from Delegated Regulation (EU) 2025/1156
Change
The CSSF stated on 22 July 2026 that Circular 21/783 becomes outdated from 23 August 2026, following ESMA's withdrawal of its Guidelines on the MiFID II/MiFIR market-data obligations, whose subject matter is now carried by Commission Delegated Regulation (EU) 2025/1156 of 12 June 2025 on making market data available on a reasonable commercial basis.
Why it matters
Circular 21/783 was the route by which the withdrawn ESMA Guidelines entered CSSF administrative practice. With the Guidelines withdrawn and their content moved into binding regulatory technical standards under Delegated Regulation (EU) 2025/1156, the intermediate layer disappears: the reasonable-commercial-basis obligations under Regulation (EU) No 600/2014 apply through the Delegated Regulation directly, without a national circular restating them. The CSSF names credit institutions, investment firms, crypto-asset service providers and specialised PFS as the entities concerned, and identifies MTFs, OTFs and trading venues as the keyword scope.
Implications
- — Luxembourg credit institutions, investment firms, CASPs and specialised PFS that cite Circular 21/783 in market-data policies, procedures or published pricing terms must repoint those references to Commission Delegated Regulation (EU) 2025/1156 before 23 August 2026, because after that date the Circular no longer states CSSF administrative practice and a policy built on it cites a superseded instrument.
- — Trading venues, MTFs and OTFs publishing market data on a reasonable commercial basis must work from the regulatory technical standards in Delegated Regulation (EU) 2025/1156 rather than the withdrawn ESMA Guidelines, since the binding form of the obligation now sits in directly applicable EU law rather than in guidance transposed through a national circular.
Who is affected
- — Luxembourg-supervised credit institutions, investment firms, crypto-asset service providers and specialised PFS
- — Trading venues, MTFs and OTFs publishing MiFIR market data
What to watch
- — Effective: 23 August 2026 — CSSF Circular 21/783 becomes outdated, and Commission Delegated Regulation (EU) 2025/1156 is the operative instrument for the market-data obligations it covered.