Identify Use Cases for Securities & Issuer ID Mapping

[toshaellison]

Please use this issue as a placeholder to identify use cases and user stories for mapping securities and issuer ID, per the discussion on the Sept 1st project meeting. (#28)

We'll look at more robust ways to capture, discuss, modify and prioritize these as they progress.

[toshaellison]

These use cases & requirements were discussed during the 10th November meeting (and likely require further elaboration).

• Requirement: Data will be accessed via API (GUI is secondary priority)
• Requirement: Need to define the mechanism by which licenses are validated when requests are made
• Requirement: Define the information to be returned if a user requests mapping information on one or more entities for which the data is available but not under the requestor's current licenses. (Return nothing? Note that data is available but only with a license? Indicate the license required?)
• Requirement: Define the process for which new data sources can be added
• Use Case: A client or regulator wants to restrict trading on a certain entity. Access the API to retrieve all identifiers for which restrictions should be put in place.
• Use Case (to be explored): Where are the key points in a trade lifecycle that this information will be required?

[sandlb]

Entity matching use case:

Securities such as bonds and equities are issued by companies (or entities). Knowing which entity issued a security is important for compliance-related functions such as calculating total exposure to or ownership of a particular entity, or determining whether a particular entity meets investor criteria such as ESG or other screens.

A challenge arises when reference data comes from different sources, and each one uses its own entity identifier. Some are open and some are licensed. A user of the system would propose a linkage between two vendor IDs for the same entity. Anyone with licensed access to both identifiers could view that linkage, and confirm or challenge that linkage. Given the linkage between two vendor IDs for the same entity, a user can then source additional attributes from their licensed data using that key. Only the keys would be provided in this system.

An example of a linkage:
Two open identifiers (could be viewed by anyone)
Open Perm ID 4295903627 = LEI 549300EJG376EN5NQE29
Open Corporates ID 2656078 = LEI 549300EJG376EN5NQE29
Open and closed (viewable only by Refinitiv subscribers; not real):
Open Perm ID 4295903627 = Refinitiv Org ID 38556
Two closed identifiers (viewable only by subscribers of both Refinitiv and Bloomberg; not real):
Refinitiv Org ID 38556 = Bloomberg ID_BB_COMPANY 211087

Due to transitivity, any ID could be mapped to any other ID given sufficient access and/or open identifiers.