Here are the ones I know for who bought who:
Not sure about the Mircom Group or some of the other “random” brands though.
Current parent companies are in red bold.
Company names with children are in black bold.
Company names with no children are black, not bold.
Defunct company names are in dark red.
Honeywell
- Gamewell-FCI (formed 2005)
- Gamewell (2003)
- Silent Knight (1999)
Pittway Corporation: (2000 by Honeywell) - Fire-Lite (unknown date)
- FCI (1997)
- System Sensor (formed 1984)
Emhart Corporation (Notifier division) (1987 by Pittway) - Notifier (1960s)
Tyco Life Safety / SimplexGrinnell
Simplex Time Recorder Company (2000 by Tyco)
- IBM fire alarm division (1958)
Grinnell (1996 by Tyco)
Thorn Security (1996 by Grinnell) - Kidde (commercial fire division only) (late 80s)
Wormald (Autocall division) (1990 by Thorn Security)
Federal Signal (Autocall Division) (1990 by Wormald) - Autocall (sometime in the 1950s or 1960s)
United Technologies
GE Security (2010 by United Technologies)
- VigilanT (formed 2007)
- FireworX (formed 2009)
SPX Corporation (EST division) (2004 by GE)
General Signal (1998 by SPX Corporation) - EST (formed 1993)
- FAST (1993)
- Edwards (1962)
- Benjamin (date unknown)
Siemens
Cerberus Pyrotronics (1998 by Siemens)
- Pyrotronics (date unknown)
- Gamewell (date unknown, later spun-off and eventually sold to Honeywell 2003)
Faraday (1995 by Cerberus Pyrotronics) - S.H. Couch Co. (1977)
- Standard Electric Time Co. (1978)