Do I need to instruct on a merger?

Only when it is sent as CHOS, which means holders can choose the consideration (for example shares or cash). A MAND merger has a single consideration and is processed without instructions.

What is the difference between MRGR and TEND?

A TEND is an offer by a third party to buy the shares; each holder decides whether to accept. A merger is a combination approved by the companies and their shareholders, and once effective it applies to every holder.

How are fractions handled in a merger?

The notification says how fractions are treated with :22F::DISF (for example rounded down with cash in lieu). The cash in lieu price is in :90a::CINL and the amount appears on the MT566.

Corporate action events

MRGR: Merger

Written and maintained by ZagTrader. Last reviewed 21 October 2026. How this page is sourced and checked

MRGR announces that two or more companies combine and the holders’ securities are exchanged for securities of the new or surviving company, cash, or a mix. It is mandatory; when holders can choose the consideration, it is sent as CHOS with a default option.

Code: MRGR
Usually announced as: MAND or CHOS

What MRGR means

In a merger the issuer’s shares disappear and holders receive the consideration agreed between the companies: new shares (SECU), cash (CASH) or both (CASE). The terms are given as a ratio of new to old (:92a::NEWO) and a price per share for any cash.

If there is only one consideration, the event is MAND. If holders may choose between considerations, it is CHOS, and a default option applies to holders who do not instruct. ASX states this rule explicitly in its ISO 20022 manual; the ECB SCoRE rulebook lists MRGR with MAND (SECU, CASE) and CHOS (SECU, CASE, CASH).

When the merger is one step of a scheme or plan of arrangement, MT564 can flag it with :22F::ADDB//SCHM in sequence D. Holders who oppose the deal may have dissenters’ rights, shown with :22F::OFFE//DISS.

When you see it

In an MT564 once the merger is approved, often after an extraordinary meeting (XMET). Key dates: effective date (:98a::EFFD), record date, payment date, and for CHOS the response and market deadlines.
MRGR vs TEND: a tender is an offer by a third party that holders may accept or not; a merger is binding on all holders once approved. MRGR vs EXOF: an exchange swaps securities without two companies combining. MRGR vs SOFF: a spin-off gives holders new shares while they keep the old ones.
A takeover often runs as a TEND first and, once the bidder has enough shares, ends with a squeeze-out or a merger to remove the remaining holders.

What to do next

For CHOS, collect the election from each beneficial owner and send an MT565 per account before the response deadline. Without it, the default option is applied.
On the MT566, reconcile the debit of the old ISIN, the credit of the new ISIN at the announced ratio, any cash, and cash in lieu of fractions (:90a::CINL or :19B::CINL). Check how fractions are handled (:22F::DISF).
Set up the new security before the payment date, move open trades and standing settlement instructions, and split the tax cost of the old position across the new consideration according to the holder’s tax rules.

Where it appears in MT and ISO 20022

MT (ISO 15022)

MT564 sequence A (GENL), :22F::CAEV//MRGR with :22F::CAMV//MAND or //CHOS
MT564 sequence E1, :92a::NEWO (new to old ratio); sequence D, :22F::ADDB//SCHM for a scheme of arrangement
MT565 and MT566 sequence A, :22F::CAEV//MRGR

MX (ISO 20022)

seev.031 CorpActnGnlInf/EvtTp/Cd = MRGR (checked in seev.031.001.15), with the flag in CorpActnGnlInf/MndtryVlntryEvtTp/Cd
The same CorpActnGnlInf/EvtTp/Cd = MRGR appears in seev.033 (instruction) and seev.036 (movement confirmation)

Questions

Do I need to instruct on a merger?: Only when it is sent as CHOS, which means holders can choose the consideration (for example shares or cash). A MAND merger has a single consideration and is processed without instructions.
What is the difference between MRGR and TEND?: A TEND is an offer by a third party to buy the shares; each holder decides whether to accept. A merger is a combination approved by the companies and their shareholders, and once effective it applies to every holder.
How are fractions handled in a merger?: The notification says how fractions are treated with :22F::DISF (for example rounded down with cash in lieu). The cash in lieu price is in :90a::CINL and the amount appears on the MT566.