CD4010
Fairchild Semiconductor
4000 Series SOIC, PDIP
Fairchild Semiconductor was one of Silicon Valley's founding chip companies, later famous for discrete transistors, MOSFETs, optocouplers, logic and power ICs. It was acquired by ON Semiconductor (now onsemi) in 2016, and many 2N, BC and KA-series datasheets carry the Fairchild name.