Common pitfalls when preparing your SFDR JSON file for the CSSF
In an increasingly digital regulatory environment, adhering to CSSF's new mandate for SFDR reporting in JSON format has become a priority for asset managers in Luxembourg. This article delves into the most common compliance challenges and provides practical strategies to help asset managers submit accurate and timely JSON reports while avoiding the common pitfalls that lead to CSSF rejections or delays.
With the Commission de Surveillance du Secteur Financier (CSSF) mandating SFDR reporting in JSON format for Luxembourg-domiciled funds, asset managers are racing to align with this machine-readable standard. However, many are encountering unexpected compliance roadblocks that can lead to CSSF rejections or delayed filings — often just days before critical deadlines.
In this article, we break down the most common pitfalls asset managers face when preparing the SFDR JSON file, and offer practical advice to avoid them.
1. Schema errors: Misaligned or incomplete JSON structure
The CSSF JSON file must adhere to a strict technical schema. Even minor deviations — like a missing field or misformatted value — can result in automatic rejections.
Examples:
- Incorrect data type (e.g., using a string instead of a number)
- Missing required fields such as isinCodes or articleCategory
- Unescaped characters in narrative text
How to avoid it:
- Always validate against the latest CSSF schema file
- Use automated tools with built-in schema validation
- Avoid manual edits unless you’re familiar with JSON syntax rules
2. Inconsistent data across submissions
The JSON file must mirror the data provided in your PDF disclosures (Annex II or V). Any mismatch between the narrative and the structured data may raise red flags during CSSF validation or audit review.
Examples:
- Asset allocation figures in JSON don't match the pie chart in the PDF
- Different taxonomy alignment percentages across formats
- Mismatched fund name or ISINs
How to avoid it:
- Create a single source of truth for all ESG data inputs
- Generate JSON and PDF from the same dataset
- Implement a reconciliation step as part of your QA process
3. Invalid or misused boolean fields
Boolean fields (true/false) are heavily used in the JSON schema, especially for compliance declarations (e.g., PAI consideration, Taxonomy alignment).
Common mistakes:
- Using "yes"/"no" instead of true/false
- Including a boolean where a string is required
- Leaving boolean fields empty or null
How to avoid It:
- Double-check data types in your mapping files
- Validate before submission using CSSF-approved tools
4. Totals that don't add up
Allocation percentages in SFDR reports must be consistent and logically complete.
Common Issues:
- Asset allocation not summing to 100%
- Missing values in the "Other" category
- Taxonomy-aligned investments exceeding total sustainable investments
How to avoid It:
- Set conditional checks in your generation logic
- Use a pre-submission checklist for mathematical consistency
5. Improper use of optional fields
The CSSF schema allows certain fields to be optional, but improper use of those fields can still lead to rejections or compliance queries.
Examples:
- Leaving optional narrative sections empty when the PDF contains content
- Including irrelevant taxonomy disclosures for Article 8 funds
How to avoid It:
- Only omit optional fields if they are truly not applicable
- Keep optional content aligned with your RTS template strategy
6. Incorrect file encoding or file name format
Sometimes the issue isn’t in the content — it’s in the way the file is packaged or uploaded.
Examples:
- Wrong file encoding (e.g., UTF-16 instead of UTF-8)
- File named incorrectly or with special characters
- Incorrect file extension or hidden formatting issues
How to avoid it:
- Use UTF-8 encoding exclusively
- Follow CSSF naming conventions (e.g., <LEI>_<submissionType>_<date>.json)
- Submit via the CSSF eDesk using the correct upload module
7. Lack of Internal Ownership and QA
Many asset managers rely on fragmented processes involving legal, compliance, ESG, and operations — leading to gaps in accountability.
Symptoms:
- Late-stage errors caught days before submission
- Miscommunication on updates to Annex templates
- No dedicated ownership of JSON validation
How to avoid It:
- Assign a dedicated owner for SFDR technical reporting
- Integrate QA and validation into project timelines
- Use collaborative platforms for real-time data review
Best Practices Summary
Conclusion: Preparation is protection
Avoiding these common pitfalls doesn’t just reduce rework — it also builds trust with regulators and demonstrates operational maturity. As SFDR requirements continue to evolve, getting the CSSF JSON file right the first time will help asset managers stay ahead of compliance pressure and streamline their ESG reporting workflows.
The FE fundinfo solution automatically applies validations to check for the correctness of a report. Therefore, it reduces time spent on finding problems and identifying the root cause for the potential issues. A professional report creation system therefore, can significantly reduce the time spent on report creation.