Is there a guarantee of uniqueness for entity beans (EJB)

Question :Is there a guarantee of uniqueness for entity beans? (EJB)
Answer :There is no such guarantee. The server (or servers) can instantiate as
many instances of the same underlying Entity Bean (with the same PK) as
it wants. However, each instance is guaranteed to have up-to-date data
values, and be transactionally consistent, so uniqueness is not required.
This allows the server to scale the system to support multiple threads,
multiple concurrent requests, and multiple hosts.