3. Buyer and seller

Every report names both the buyer and the seller, and who they are depends on the capacity your firm acted in. On a DEAL trade, where your firm's LEI sits shows whether it bought or sold.

Your capacity decides who appears

You acted as	Meaning	Buyer and seller
DEAL	On your own account, taking the risk	Your firm is one side; the other side is your counterparty or client
MTCH	Matched principal: two simultaneous back-to-back trades, no risk	Your client and the market counterparty; not your firm
AOTC	Any other capacity, usually agency for a client	Your client and the market counterparty; not your firm

A common mistake is to show your own firm as buyer or seller on an agency trade. Our checks will warn you if that happens.

The transmission of order indicator

You don't need to supply this one, because we work it out from your capacity and venue. It is N for DEAL and MTCH. For AOTC it is Y, unless you executed on a venue yourself under your own membership, in or outside the UK and EU.

Who is "the market"?

On a venue with a central counterparty (CCP), such as the London Stock Exchange for shares, the other side is the CCP: give its LEI.
Off venue, it is the firm you traded with: give its LEI.
Only on a venue without a CCP, where you never learn the counterparty, do you give the venue's MIC. In the UK that is rare.

Identifying people

When a buyer or seller is a person, use their national identifier, in the FCA's order of preference for their nationality:

UK nationals: National Insurance number, with GB in front, for example GBQQ123456C, type NIDN.
Other nationalities: the identifier the FCA lists for that country first (sometimes a passport number, type CCPT).
Where none applies: the CONCAT code, type CONCAT.

Building a CONCAT code

It is 20 characters, in capitals, in this order:

The two-letter country code of the person's nationality.
Their date of birth as YYYYMMDD.
The first five letters of their first name.
The first five letters of their surname.

A name longer than five letters is cut to five. A shorter one is padded with #, so John becomes JOHN#. Leave out titles and surname prefixes such as van, de or mac, and remove accents, apostrophes, hyphens and spaces.

For example, John Smith, British, born 30 October 1980, is GB19801030JOHN#SMITH. Anne-Marie de Vries, Dutch, born 12 March 1975, is NL19750312ANNEMVRIES.

Give the person's full first names, surname and date of birth in their own columns too.

Clients

Mark buyer_is_client or seller_is_client with Y for your clients. We use it to fill in the FCA's "country of the branch" field for you.

Decision makers

If your firm manages a client's money with discretion, your firm made the decision for the client: put your own LEI as the client's decision maker. If a person with a power of attorney decided, put their identifier. If the client decided, leave it blank.

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