noun which may take the genitive case particle 'no'
unauthorized; without permission; unapproved
Used as a no-adjective to describe actions or things done without official permission.
無許可で工事を始めてはいけません。
You must not start construction without permission.
無許可のコピーは法律違反です。
Unauthorized copying is a violation of the law.
noun
lack of permission; absence of authorization
Used as a noun to refer to the state of not having permission. Often appears in formal or legal contexts.
無許可が問題となった。
The lack of permission became an issue.