
Hi @SHUO .H
Per my test, when set unique permission for document library B1 and B2 like you mentioned, Aaronp access the (A1): He can see B1, B2, B3 documents. Adamb access the (A1): He can see B2, B3 documents. Danb access the (A1): He can see B3 document. Yex access the (A1): She can see B3 document.
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