Patent ID: 7756894

Claim:
An information search apparatus, comprising: a processor; a storage device associated with a document information manager; and a search device configured to: receive identity information corresponding to a current user and keyword information input by the current user; retrieve access level information corresponding to the current user indicating a highest confidentiality level of documents that the current user is authorized to access; use the processor to identify a set of documents stored in the document information manager matching the keyword information input by the current user, and from that set, at least one document having a confidentiality level higher than that of the current user and that the current user is therefore not authorized to access; indicate to the current user that at least one document has been identified that the current user is not authorized to access; for at least one of the documents identified that the current user is not authorized to access, use access log information indicating when and by whom each document stored in the document information manager has been previously accessed to identify at least one previous user with a higher confidentiality level who has accessed the at least one document; and use keyword log information indicating when and what keywords were used in previous searches executed by the search device to identify at least one previous user who has used the same keyword information input by the current user, wherein the search device is configured to select previous users to be familiar to the current user by analyzing user network information that indicates the relationships between registered users of the document information manager.