Third party
From ACT Wiki
1. Law - contract - legal proceedings - agreements - other arrangements - noun.
A person or other entity not directly involved in a contract, transaction or legal proceedings.
2. Other situations - noun.
Any person, group, organisation or other entity not primarily involved in a situation between two other people, groups, organisations or other entities.
3. Law - contract - legal proceedings - agreements - other arrangements - other situations - adjective.
Relating to such a person or entity.
Usually written third-party.
For example, KY3P refers to knowledge and understanding of third-party risk in relation to transactions.
Third parties would include, for example, suppliers as well as customers.