CSSF UCITS Merger Application Forms: A Filing Guide for Luxembourg Fund Teams

Updated July 2026

A UCITS merger submitted to the CSSF without the required Article 67 information is not a complete application. The CSSF UCITS merger forms now sit at the front of that process, and the decision clock the regulator runs against your file only starts once the file is judged complete. Get the package wrong and you lose days against an effective date the board, the depositary, and the project team have already planned around.

On 19 June 2026 the CSSF published two new application forms for UCITS mergers: one for domestic mergers under the Law of 17 December 2010, and one for outbound cross-border mergers where the receiving UCITS sits in another Member State under Directive 2009/65/EC. Both are Excel workbooks, and the CSSF states their use is mandatory for all new applications submitted from the date of publication. This note maps what the forms change, the procedure they sit inside, and where filing teams lose time.

Related reading: CSSF AIF and ELTIF marketing notification letter

What the CSSF UCITS merger forms actually cover

There are two separate workbooks: an application form for the authorisation of a UCITS domestic merger under the Law of 17 December 2010, and an application form for the authorisation of a UCITS outbound cross-border merger where the receiving UCITS is established in another Member State under Directive 2009/65/EC. Both are XLSX files of roughly 125 kilobytes. The notice is short and operative: the forms must be duly completed and submitted with all documents required under the applicable regulations to amendments.uci@cssf.lu, and their use is mandatory for all new applications submitted from the date of publication. There is no transitional window and no grandfathering for applications you were about to send in free format.

One distinction is easy to skip. The two forms cover the domestic case and the outbound case where Luxembourg is the home of the merging UCITS. They are not framed around an inbound merger where the receiving UCITS is the Luxembourg fund and the merging UCITS sits abroad. That scenario still runs through the procedure, but it is not what these workbooks are built around.

The procedure the form sits inside

The procedure for a Luxembourg merging UCITS turns on a completeness assessment, and the form is the regulator’s way of forcing the completeness question to the front. Where the merging UCITS is established in Luxembourg, the merger is subject to prior authorisation by the CSSF under Article 67 of the Law of 17 December 2010. Article 67 also lists what the merging UCITS provides: the common draft terms duly approved by the merging and receiving UCITS, an up-to-date prospectus and key investor information of the receiving UCITS where it is in another Member State, a statement by each depositary of the merging and receiving UCITS, and the information on the proposed merger intended for unit-holders.

Here is where teams misread the timeline. The twenty-working-day decision period in Article 67, within which the CSSF tells the merging UCITS whether the merger is authorised, runs from submission of the complete information, not from the day you first email the package. If the CSSF considers the file incomplete, Article 67 lets it request additional information within a maximum of ten working days, and the decision clock waits for the complete-file date. A well-built form is the cheapest insurance against that delay.

The form does not replace the substance of Chapter 8 of the Law of 17 December 2010; the CSSF reviewer is checking the same articles. Article 66 confirms that a Luxembourg UCITS may act as a merging or receiving UCITS in domestic and cross-border mergers and that the merger provisions of the 1915 company law do not apply. Article 69 sets out the common draft terms and their particulars: the type of merger and the UCITS involved, the background and rationale, the expected impact on unit-holders, the valuation criteria for assets and liabilities, the calculation method of the exchange ratio, and the planned effective date. Two control steps sit alongside them. Under Article 70, the depositaries of the merging and receiving UCITS established in Luxembourg verify the conformity of specified particulars. Under Article 71, the merging UCITS established in Luxembourg entrusts either an approved statutory auditor (a réviseur d’entreprises agréé) or an independent auditor to validate the valuation criteria, any cash payment per unit, and the calculation method and actual exchange ratio. These are not optional control steps. The form package must support the CSSF’s assessment that the merger complies with Articles 67, 69, 70 and 71; the Article 71 report must be available on request to unit-holders and the competent authorities.

Information to unit-holders and the redemption window

The part of a merger most likely to generate complaints is the unit-holder communication, governed by a sequencing rule that teams break more often than any single template field. Under Article 72, where the merging or receiving UCITS is established in Luxembourg, each provides appropriate and accurate information on the proposed merger so unit-holders can make an informed judgement. The trap is Article 72: that information may be provided only after the CSSF has authorised the merger. Sending the unit-holder letter before authorisation is a common and avoidable error. The information must reach unit-holders at least thirty days before the last date for requesting repurchase, redemption, or conversion without additional charge, and Article 72 fixes its content, down to a prominent warning where tax treatment may change and a copy of the receiving UCITS key investor information.

Under Article 73, unit-holders may request repurchase, redemption, or conversion without charge beyond disinvestment costs; that right ceases five working days before the exchange-ratio calculation date under Article 75(1). Under Article 74, legal, advisory, and administrative costs are not charged to the merging or receiving UCITS or their unit-holders, except where no management company has been designated. Article 76 records the consequences by merger technique: for Article 1(20)(a) and (b) mergers, assets and liabilities transfer and unit-holders may receive a cash payment not exceeding 10% of net asset value; for Article 1(20)(c) mergers, net assets transfer and the merging UCITS continues to exist until liabilities are discharged. The 10% cash ceiling applies where a cash payment is used under the relevant merger technique; it is not a planning convenience.

Where filing teams lose days

The first error is treating the form as the deliverable. It is not. The notice is explicit that the form is submitted together with all documents required under the applicable regulations. A fully filled workbook is not enough if the Article 67(2) documents are missing. If the CSSF considers the file incomplete, Article 67 allows it to request additional information within ten working days of receipt. The second is the channel: submissions go to amendments.uci@cssf.lu, the address the CSSF names. Teams that already run other CSSF interactions, such as the CSSF AIF and ELTIF marketing notification process, will recognise that a named channel is part of the requirement.

The third is the cross-border reading. The outbound form applies where Luxembourg is the merging UCITS. Once the file is complete, the CSSF transmits copies to the receiving state’s competent authorities, who may require the receiving UCITS to modify its unit-holder information within fifteen working days. Build the calendar to accommodate both that step and the CSSF’s twenty-working-day decision. The fourth is assuming the unit-holder letter can be issued in parallel to save time. Drafting it in parallel is sensible. Issuing it before authorisation is the Article 72 breach.

Frequently Asked Questions

When did the new CSSF UCITS merger forms become mandatory?

The CSSF published them on 19 June 2026 and states their use is mandatory for all new applications submitted from the date of publication. The notice gives no transitional period.

Which form do I use for a domestic versus an outbound cross-border merger?

The domestic merger form covers mergers under the Law of 17 December 2010. The outbound cross-border form covers the case where the merging UCITS is the Luxembourg fund and the receiving UCITS is in another Member State under Directive 2009/65/EC. Both are XLSX workbooks, submitted with all required supporting documents to amendments.uci@cssf.lu.

How long does the CSSF have to decide on a UCITS merger?

Under Article 67 of the Law of 17 December 2010, the CSSF decides within twenty working days of submission of the complete information. If the file is incomplete, Article 67 allows the CSSF to request more information within a maximum of ten working days of receipt, and the decision period runs from the complete-file date.

Can we send the unit-holder information at the same time as the application?

No. Under Article 72, the information may be provided to unit-holders only after the CSSF has authorised the merger, and it must reach them at least thirty days before the last date for redemption without additional charge under Article 73.

Related Articles

• CSSF AIF and ELTIF marketing notification letter – How the CSSF notification letter process works for AIF and ELTIF marketing in Luxembourg.
• AIFMD II Annex IV reporting changes – What changes for alternative fund manager regulatory reporting under the revised AIFMD framework.
• DORA compliance checklist for Luxembourg fund administrators – An operational checklist for fund administration teams meeting the DORA ICT resilience requirements.
• CSSF reporting calendar Q3 2026 – The Luxembourg supervisory reporting deadlines that fund and bank teams track each quarter.
• CSSF MMFR FAQ update for Luxembourg money market funds – How the CSSF clarified money market fund obligations in its updated MMFR FAQ.

Key Takeaways

• The CSSF published two new UCITS merger application forms on 19 June 2026: one for domestic mergers under the Law of 17 December 2010, one for outbound cross-border mergers under Directive 2009/65/EC.
• Use of the forms is mandatory for all new applications from the publication date, with no transitional window, and both are XLSX workbooks submitted with all required documents to amendments.uci@cssf.lu.
• The twenty-working-day decision period under Article 67 runs from the complete file, not first submission; an incomplete file triggers a ten-working-day additional-information request under Article 67, which implements the Directive’s Article 39 procedure.
• Unit-holder information may only be issued after CSSF authorisation under Article 72 and must reach unit-holders at least thirty days before the last redemption date.
• Unit-holders hold a redemption or conversion right under Article 73 with no charge beyond disinvestment costs, ceasing five working days before the exchange-ratio calculation date.
• The common draft terms, the Article 67(2)(c) depositary statement, and the Article 67(2)(d) unit-holder information form part of the submitted file; Article 71 validation remains a separate control requirement, and outbound mergers must also factor in the receiving authority’s fifteen-working-day review step under Article 67.

Sources and References

• CSSF, Publication of two new forms relating to proposals for UCITS domestic merger (Law of 17 December 2010) and outbound cross-border merger with the receiving UCITS in another Member State (Directive 2009/65/EC), 19 June 2026: CSSF notice
• Law of 17 December 2010 relating to undertakings for collective investment (consolidated text), Chapter 8 (Mergers of UCITS), Articles 65 to 76: CSSF, Law of 17 December 2010 (PDF)
• Directive 2009/65/EC (UCITS Directive), Chapter VI (Mergers of UCITS), Articles 37 to 48: EUR-Lex, Directive 2009/65/EC

Filing the merger, not just the form

The two forms pull the completeness test to the front of the queue. The procedure in Chapter 8 of the Law of 17 December 2010 has not changed. What has changed is that the workbook now records, field by field, whether the application supports the CSSF’s completeness and authorisation checks, including the Article 67 documents, depositary verification, Article 71 validation process, and unit-holder information. Treat the form as a checklist against Articles 67 to 76, sequence the unit-holder letter after authorisation, and the clock starts when you want it to start.

Disclaimer: The information on RegReportingDesk.com is for educational and informational purposes only. It does not constitute legal, regulatory, tax, or compliance advice. Always consult your compliance officer, legal counsel, or the relevant supervisory authority for guidance specific to your institution.