noun
Formal term for a person who makes an application or proposal, often in legal, administrative, or official contexts.
申出者が提出した書類を審査します。
We will examine the documents submitted by the applicant.
申請者 is a more common and general word for 'applicant', while 申出者 is more formal and often used in specific legal or procedural contexts.
Compound of 申し出 (もうしで, 'proposal, offer') + 者 (しゃ, 'person'). The kanji spelling 申出者 is a variant without the okurigana し.