Lamp Manufacturers in Warren, Ohio
Warren, Ohio certainly must be unique in that, for its size, it probably had more manufacturers of electric incandescent lamps than any other city. The following companies manufactured electric incandescent lamps in Warren during the specified times. The information that follows was taken from the Warren City Directories:

1891-92
The New York & Ohio Co. (used the Packard label)
1893-94
The New York & Ohio Co.
The Warren Electric & Specialty Co.
1899
The New York & Ohio Co.
The Warren Electric & Specialty Co.
1904
The Economy Electric Co.
The Monarch Electric Mfg. Co.
The New York & Ohio Co.
The Peerless Electric Co.
The Standard Electrical Mfg. Co. (Niles)
The Sterling Electrical Mfg. Co.
The Warren Electric & Specialty Co.
1906
The Economy Electric Co.
Mahoning Lamp Factory
The Monarch Electric Mfg. Co.
The New York & Ohio Co.
The Peerless Electric Co.
The Standard Electrical Mfg. Co. (Niles)
The Sterling Electrical Mfg. Co.
The Warren Electric & Specialty Co.
The Holscher Electrical Mfg. Co. (lamp renewer)
The Niles Electric Co. (Niles) (lamp renewer)
1908
The Colonial Electric Co.
The Economy Electric Co.
The Holscher Electrical Mfg. Co.
The Monarch Electric Mfg. Co.
The New York & Ohio Co.
The Niles Electric Co. (Niles)
Ohio Lamp Works
Mahoning Lamp Works
The Standard Electrical Mfg. Co. (Niles)
The Sterling Electrical Mfg. Co.
The Warren Electric & Specialty Co.
1910
The Aladdin Electric Co.
The Colonial Electric Co.
The Economy Electric Co.
Hecklinger Electric Co.
The Holscher Electrical Mfg. Co.
Mahoning Carbon Lamp Works
The New York & Ohio Co.
The Niles Electric Co.
Ohio Lamp Works
Refilled Carbon Lamp Works (Niles)
The Standard Electrical Mfg. Co.
The Sterling Electrical Mfg. Co.
Trumbull Carbon Lamp Works
Trumbull Mazda Lamp Works
The Warren Electric & Specialty Co.

The United States Circuit Court, Northern District of Ohio, Eastern Division, on Oct 12, 1911, required that several lamp manufacturing plants, which were owned by the General Electric Company, henceforth inform the public of the relationship that existed between them and GE. It will be seen below that those plants became identified as being Divisions of GE.

1914
Colonial Electric Division
The Holscher Electrical Mfg Co.
Mahoning Mazda Lamp Division
Ohio Division
Packard Lamp Division
Peerless Lamp Division
Standard Electric Division
Sterling Electric Lamp Division
Trumbull Mazda Lamp Division
1916
Colonial Electric Division
International Lamp Co
Novelty Lamp Co
Mahoning Miniature Lamp Division
Ohio Division
Packard Lamp Division
Peerless Lamp Division
Standard Electric Division
Sterling Electric Lamp Division
Trumbull Mazda Lamp Division
1919
Colonial Electric Division
Mahoning Miniature lamp Division
Ohio Division
Packard Lamp Division
Peerless-Brilliant Lamp Division
Standard Electric Division
Sterling Electric Lamp Division
Sunlight Electrical Mfg Co. (organized in Jun 1917)
Trumbull Mazda Lamp Division
1921
Colonial Electric Division
Ohio Division
Packard Lamp Division
Peerless-Brilliant Lamp Division
Standard Electric Division
Sterling Electric Lamp Division
Sunlight Electrical Mfg Co
Trumbull Mazda Lamp Division
1923
Ohio Division
Packard Lamp Division
Peerless-Brilliant Lamp Division
Sterling Electric Lamp Division
1925
Ohio Mazda Lamp Works
Packard Lamp Division
Peerless-Brilliant Lamp Division
Sterling Electric Lamp Division
1927
Ohio Lamp Works of General Electric Co.