Acts 4:6

Amplified Bible

⁶and ^[a]Annas the high priest was there, and ^[b]Caiaphas and ^[c]John and Alexander, and all others who were of high-priestly descent.

Acts 4:6 Annas served as high priest a.d. 6-15. He was removed from the position by Rome, but continued to be extremely influential and was regarded by the Jews as de facto high priest even though others (his sons and son-in-law) officially held the office.
Acts 4:6 Caiaphas (Annas’ son-in-law) served as high priest a.d. 18-36.
Acts 4:6 Perhaps this is Jonathan, one of Annas’ sons.