R&D Div. #1 (第一研究開発本部), also called SIC R&D1 (SIC第一研究開発本部) was the first arcade division of Sega Interactive. It was the successor to Sega R&D1.

R&D3 was founded around the same time as this iteration of R&D1, primarily composed of previous R&D1 staff and taking with it some previous R&D1 franchises. The new R&D1 kept StarHorse , Initial D, Sangokushi Taisen/Sengoku Taisen, Code of Joker and Chain Chronicle. However, there seems to have been some continued collaboration with R&D3 staff, at least on the sound side, seen with Takenobu Mitsuyoshi on StarHorse and Takahiro Kai on Chain Chronicle.

It was merged with Sega Games in 2020, becoming a new department in the 5th Development Div. of Sega Asia & Japan Studio HQ.