ESMA FIRDS: how reference data determines MiFIR reportability, and where it stops

This article is for informational purposes only and does not constitute legal advice. Consult a qualified legal professional for advice specific to your situation.

What a FIRDS record is evidence of

The Financial Instruments Reference Data System is the mechanism through which Article 27 of MiFIR operates. Trading venues must supply identifying reference data for instruments admitted to trading on regulated markets or traded on MTFs or OTFs. Systematic internalisers must supply reference data for the other instruments covered by Article 26(2) that are traded on their systems. The data is supplied for the purposes of transaction reporting, which is the reason FIRDS exists at all.

That purpose explains what a record can and cannot show. A record shows that a venue or systematic internaliser has reported the instrument as admitted to trading or traded there, with identifying attributes such as its ISIN, classification and currency. It does not certify that an investment firm's trade in that instrument was reported correctly, and it does not certify that the instrument is the only route into reporting scope.

The directory on this site makes the published data searchable by instrument, venue, issuer and asset class. What a result means depends on the legal test it feeds into, which the next section sets out.

Why reportability is a legal test and not a lookup

Article 26 requires investment firms that execute transactions in financial instruments to report complete and accurate details to the competent authority. Article 26(2) limits that obligation to four categories: instruments admitted to trading or traded on a trading venue, or for which a request for admission has been made; instruments whose underlying is a financial instrument traded on a trading venue; instruments whose underlying is an index or basket composed of financial instruments traded on a trading venue; and the OTC derivatives referred to in Article 8a(2).

The first category is the one FIRDS evidences directly. The second and third are why a "not found" result needs care: a derivative whose underlying is a venue-traded share is reportable under the second category even if no venue has reported the derivative itself, and one whose underlying is a venue-traded index or basket is caught by the third. The fourth covers the OTC derivatives referred to in Article 8a(2), which the 2024 amendments brought within the reporting obligation. In practice, a hit in FIRDS settles the first limb quickly. A miss sends the analysis to the underlying, and only after that can a firm conclude the instrument is out of scope.

Why one ISIN can appear many times

FIRDS records are keyed on the combination of ISIN and the market identifier code of the venue. Where an instrument is admitted to trading or traded on several venues, it has several records, one per venue.

Two consequences follow for anyone reading the directory. First, the headline figure of distinct ISINs is the right number for "how many instruments exist in the dataset", while the per-venue figures count listings. They answer different questions. Second, an instrument with a long list of venues is not duplicated data. Each record is a statement by a different venue or systematic internaliser, and the attributes can differ between them.

The practical point for data teams is to decide which question they are asking before choosing which count to use. Reconciling an internal security master against FIRDS should normally be done on ISIN, with the venue dimension treated as a separate attribute.

What the venue figures do and do not show

At any given publication date, FIRDS holds millions of instrument records across several hundred active venues. The distribution is extremely uneven: a small number of venue codes account for the large majority of listings, while most venues carry far fewer.

It would be a mistake to read those figures as a ranking of market importance. Article 27 brings systematic internalisers into the reference data regime alongside regulated markets, MTFs and OTFs, and instrument counts at a venue code reflect what that operator chooses to list or quote, including large populations of derivatives and structured products. A venue with a very high count may carry little trading in most of its instruments. Reading a MIC properly means checking what type of venue it identifies in the ISO 10383 register, and then looking at transparency and volume data, not instrument counts, to judge activity.

The issuer count carries the same kind of limit. It counts issuers of bonds and equity for which LEIs are published, and it does not cover derivatives issuers or the many instruments that carry no issuer LEI.

Timing: what the publication date tells you

The directory states its publication date for this reason: a result shows the position as of that publication, not the position at the moment of your search.

Article 27 requires reference data to be made ready for submission before trading commences in the instrument, but there is still a lag between an event at the venue and its appearance in a published snapshot. Instruments that are terminated or corrected will drop out or change in later snapshots, so a record seen last week may no longer be current.

For a firm validating transaction reports, that lag matters most around new listings and corporate actions. If a report is rejected or an instrument cannot be found, the first check is whether the instrument is newer than the latest published snapshot, before concluding that the data is wrong.

What is changing

Regulation (EU) 2024/791 amended MiFIR, including Article 27, and entered into force on 28 March 2024 after adoption on 28 February 2024 and publication in the Official Journal on 8 March 2024. Article 27(1) now requires each designated publishing entity to supply identifying reference data for OTC derivatives within Article 26(2) that no trading venue has reported, and empowers the Commission to adopt a delegated act specifying that reference data. That is the part of the instrument universe FIRDS has historically not covered, so its implementation bears directly on the scope gap described above.

Separately, RTS 23 (Commission Delegated Regulation (EU) 2017/585), which sets the content and format of reference data, is the instrument to check for the current field lists described here.

For the supervisory structure behind these mandates, see ESMA, EBA, EIOPA: who does what in EU financial supervision. For how the same reference data feeds market data consolidation, see Parsing the MiFIR consolidated tape: data requirements for DRSPs.

Using a FIRDS lookup well

Start with the ISIN, not the name, because names vary across venues. If the instrument is found, note which venues report it and the publication date of the data. If it is not found, do not stop: identify the underlying and test the remaining limbs of Article 26(2). Keep a record of the date and the result, because reference data changes and a later review may need to show what the position was when the decision was made.

The directory is a search aid over published data. It is not a determination of reportability and it does not replace the firm's own assessment against the regulation.

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