noun
issuer; publisher
Refers to a person or organization that issues or publishes something, such as documents, certificates, securities, or publications.
この証明書の発行者は市役所です。
The issuer of this certificate is the city office.
その本の発行者は大手出版社だ。
The publisher of that book is a major publishing company.
出版社 specifically refers to a publishing company, while 発行者 can be any issuer, including of certificates or securities.
Compound of 発行 (issue, publish) and 者 (person).