According to the Copyright Act of the Republic of China (Taiwan):

Article 32 Economic rights in a pseudonymous work or an anonymous work endure for fifty years from the time of public release; provided, the economic rights shall be extinguished where it can be proven that the author has been deceased for over fifty years.

The provisions of the preceding paragraph shall not apply when the pseudonym of the author is well known to the public.

Article 33 Economic rights in works authored by a juristic person endure for fifty years after the public release of the work; provided, if the work is not publicly released within fifty years from the completion of the creation, the economic rights shall subsist for fifty years after completion of the creation.

依中華民國《著作權法》：

第三十二條 (別著著作或不具名著作之著作財產權存續期間)

　　別名著作或不具名著作之著作財產權，存續至著作公開發表後五十年。但可證明其著作人死亡已逾五十年者，其著作財產權消滅。 　　前項規定，於著作人之別名為眾所周知者，不適用之。

第三十三條 (法人為著作人之著作財產權存續期間)