noun
finder of lost property
Refers to the person who finds and holds lost property, often in legal or formal contexts such as the Japanese Lost Property Law.
拾い主は落とし主に品物を返さなければならない。
The finder must return the item to the owner.
拾い主が現れない場合、品物は警察に届けられる。
If the finder does not appear, the item is handed over to the police.