B-4
- Full Name: Data
- Constructed: Early 2330s (Star Trek: Nemesis)
- Species: Soong-type android
- Gender: Male-presenting
- Father: Noonien Soong
- Brother: Lore
- Brother: Data
- November 2379: Discovered, subverted by Shinzon as part of running plan (Star Trek: Nemesis)
- Memories of Data uploaded into B-4's matrix shortly before his death (Star Trek: Nemesis)
- March 2380: Remanded to Daystrom Institute (TNG Novel: Resistance)