The Enforcement Rules of the Immigration Act Article 6
Those who already entered the State may authorize others or immigrations service organizations to apply for residence, change the purpose of residence, residence extension, permanent residence, or registered permanent residence.Should applications referred to in the previous paragraph be filed by legal guardian of the applicant, the authorization documents may be exempted.
中文原文 入出國及移民法施行細則第6條
已入國者，得以書面委託他人或移民業務機構代辦申請居留、變更居留原因、延期居留、永久居留或定居事項。
前項申請案件，由法定代理人辦理者，免檢附書面委託文件。
前項申請案件，由法定代理人辦理者，免檢附書面委託文件。