More recently, a revision of the U.S. copyright Act in 1976 extended copyright protection to unpublished works and codified what constitutes "fair use."

更近一点，1976年美国对Copyright Act的修订，将版权扩展到保护未出版的作品，并编写了“正当使用”的条款。

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New hope came with the passage of the Copyright Act of 1976, and certain amendments to the law in 1999, which provided limited rights to creators such as Siegel and Shuster, and their heirs, to reclaim copyrights.

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The framers of the 1976 Copyright Act took counsel from publishers, the recording industry, broadcasters and others with a vested interest in preserving the status quo.

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