When you create an instrument, LUSID automatically generates a LUSID Instrument ID (also known as a LUID), for example LUID_3L7Z8RWD.
A LUID is an internal identifier that is guaranteed to be unique to your domain and never change. You cannot edit or delete an instrument's LUID. If you have chosen to partition your LUSID instrument master into scopes, an instrument's LUID is unique across all scopes, even if the 'same' instrument exists in multiple scopes.
A LUID has:
An identifier type of LusidInstrumentId
A 3-stage key of Instrument/default/LusidInstrumentId (you may need to address the instrument using this key)
A value that starts with LUID_ for a non-currency instrument
A value that starts with CCY_ for a currency instrument.
The following LUIDs are reserved:
LUID_ZZZZZZZZ for the unknown instrument
CCY_ZZZ for the unknown currency
CCC_XXX for a 'transaction' involving no currency.