Patent ID: 6965996

Claim:
A data management method for distributing digital content in which annex information is visibly arranged, the data management method comprising: a step of duplicating as a discrete data unit a part of said digital content including a position where said annex information is visibly arranged, and encrypting the discrete data unit to create an encrypted discrete data unit; a step of embedding within said digital content as invisible information image-compositing information, relating to position and size for arranging said annex information in said digital content, and authorization information, including encryption key information by which said discrete data unit is encrypted, to create an authorization information-added data unit; a step of visibly arranging said annex information in a position corresponding to the discrete data unit for said authorization information-added data unit, to create an annex information-added data unit; and a step of creating and distributing composite data composited from said encrypted discrete data unit and said annex information-added data unit.