Purpose. The article proposes an approach to protection against unauthorized access to information about services, enterprise management, financial activities, business planning, marketing ideas, customer bases, technological strategies, production technology and recipes, other confidential information that is a commercial secret of the enterprise. This approach involves several IT tools usage, as electronic digital signature and steganographic algorithms. The electronic digital signature

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... onality is described. Methodology. The method of using an electronic digital signature is schematically shown. The connection between digital watermarks and the electronic digital signature is offered. The description of requirements to digital watermarks is executed. A method of authentication using an electronic digital signature is proposed, which allows proving the authorship during the examination. Results. The article describes a mathematical algorithm for embedding a digital watermark, using a secret key, timestamps, steganographic file system StegFS for Linux, hiding data in file formats unused areas, substituting characters in file names, text steganography. Using reserved fields of computer file formats -the essence of the method is that the part of the extension field that is not filled with information about the extension, by default is filled with zeros. Originality. The method of using special properties of format fields that are not displayed on the screen is based on special "invisible" fields to obtain footnotes, pointers. During the experimental verification of the simultaneous use of several technical security measures (digital watermark, electronic digital signature and timestamp), a significant result was obtained, which suggests an increase in the level of electronic document security in the system provided the organization and use of such protection. Practical value. Today's common steganographic methods of protecting raster images for embedding stable digital watermarks are mainly based on the statistical and physiological redundancy usage.