Iseya Shoten is currently led by the fourth-generation brewmaster, Shutaro Kobayashi. After studying at Japan's National Research Institute of Brewing in Hiroshima, he continued his training in 2002 under the guidance of experienced toji (master brewer) Yutaka Okada, among others, learning the fundamentals of sake brewing, including koji-making. While honoring the traditions established by his predecessors, he strives every day to craft sake that reflects his own vision."​​​​​ Announced closure of business in 2025.