Suzuki Mosaburō became the general secretary of the party.
[1] Yamakawa and Sakai Toshihiko functioned as 'elder' advisors in the party.
Other prominent founders of the party were Kuroda, Inamura Junzo and Okada.
[2][3] The Proletarian Masses Party claimed to have around 2,500 members.
At the time of its foundation, the party declared its intention to struggle against leftwing sectarianism and rightwing disruptionism.