I found it easier to remember that EEFs come from outside the organization/project, while OPAs are internal to the organization/company/project. Specifically to answer your question:
1. A Code of Ethics is created by a professional organization (such as PMI) and not each individual company. A Code of Ethics tells you what is expected, not HOW to meet those expectations. Therefore it is an EEF.
2. An Ethics Policy is a statement created by a company specifying HOW they will abide by an Ethics Code. It is specific to the company or organization, therefore it is an OPA.
3. Past experience with a seller is effectively how the seller treats you - you cannot control it and it comes from outside the organization. Therefore it is an EEF.
4. A performance report of a seller is your evaluation of the seller's activities and is created by your company/organization - therefore it is an OPA.
I have doubts regarding a few documents. They are very similar. Can you please explain the difference?
If a question comes, suppose, how to review the past performance of a seller, should we refer EEF or OPA ?
1. Code of ethics, is EEF.
2. Ethics policies, is OPA.
3. Past experience with a seller, is EEF.
4. Performance report of a seller, is OPA.
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