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Revision with unchanged content. The advent of digital and network technologies have brought both opportunities and threats to right-holders and users of copyrighted works. The legal reaction to these changes has been to expand the scope of copyright and outlawing circumvention of DRM technologies. As a result, society now suffers two major problems: the problem of diminishing freedoms that were built into the copyright regime in the past, and the tragedy of the anticommons (or underuse of copyrighted works caused by holdouts among multiple right-holders). To articulate these problems, this book analyzes four major areas of copyright that show clear contrasts between the U.S. and Japan: regulations over temporary data storage in computer memory devices; legal structure of copyright exemption; regulations over DRM technologies; and registration and licensing schemes as a possible solution to the tragedy of the anticommons. The research is made from a legal, economic, and technological perspective, with interview results in the market. This book is addressed to policy makers, legislators, and market players in the field of copyright who want to understand how digital copyright issues can be better approached.

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J.S.D. (Doctor of Science of Law, Stanford Law School): studies of intellectual property law (including comparative studies between Japan, U.S. and Europe), particularly copyright law in digital network environment. Attorney-at-law, Mori Hamada & Matsumoto, Tokyo, Japan; Visiting Associate Professor, National Institute of Informatics.

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