Reporting Handbook for Investment Firms

1. Overview & Purpose
The Reporting Handbook for Investment Firms, updated on 31 March 2025, consolidates guidance for both European (IFR/IFD) and national reporting requirements in a single resource. It provides clear instructions on formats, timelines, templates, XBRL specifications, and file submission methods that investment firms under Luxembourg supervision must follow.

2. Scope & Classification
Under the EU IFD/IFR framework, investment firms are classified into:

• Class 1 IF: Systemically important firms or those subject to CRR/CRD, which continue reporting under applicable credit institution regimes.

• Class 2 and Class 3 IF: Smaller and non-interconnected firms subject to proportionate IFR reporting. The Handbook applies to these firms and their Luxembourg branches, as well as branches of third-country investment firms operating in Luxembourg.

3. Reporting Requirements
The Handbook presents a structured overview of required reporting by firm class, including:

• Frequency and timelines:

  • Monthly, quarterly, semi-annual, or annual reporting depending on templates and firm class.

• Template types:

  • European IFR templates cover metrics such as own funds, K-factors, concentration and liquidity risk, activity thresholds, and capital requirements.

  • National reporting includes financial situation, off-balance-sheet commitments, profit & loss, staff numbers, and ad hoc statistical data.

4. Technical & Submission Specifications

• Reports must follow specific XBRL-XML formats as defined by the EBA, with particular naming conventions for .zip and .xbrl files using accounting and versioning codes (e.g., L, N, S, C for consolidation levels; N/D for preliminary/final).

• A “no partial reports” policy applies—each submission must be complete and will fully replace prior reports.

• Reports must be submitted via an S3-compatible secure channel (or HTTPS), with file naming conventions strictly enforced.

5. Updates & Flexibility
The March 2025 update (version 1.4) introduces:

• Minor changes in templates for Class 2 firms.

• Clarifications about adjusting reporting reference and submission dates for firms whose fiscal year ends on dates other than 31 December.

6. Testing & Support

• CSSF offers an optional "Echo Service": a connectivity test allowing firms to verify secure file transfer before going live.

• For guidance or technical support, firms can contact CSSF at specific email addresses for reporting and technical issues.

Why This Matters

• Streamlines compliance: Separates reporting obligations by firm class, reducing complexity for smaller firms.

• Ensures data integrity: Standardized XBRL formats, strict file naming, and no-partial submission policy reinforce accuracy.

• Adapts to firm needs: Versioning flexibility and testing tools help smooth transitions and ensure readiness.

• Consolidates guidance: Bringing EU IFR mandates and national requirements together simplifies reference and implementation.

https://www.cssf.lu/wp-content/uploads/Reporting_Handbook_IFR.pdf