| Akron Rubber Reclaiming | Akron | OH |
| Akron Rubber Reclaiming | Barberton | OH |
| Akron Safety Building | Akron | OH |
| Akron Standard | Barberton | OH |
| Akron Standard | Akron | OH |
| Akron Steam Heating | Akron | OH |
| Akron Steel Treating | Akron | OH |
| Akron Street Railway & Illuminating | Akron | OH |
| Akron Thermal | Akron | OH |
| Akron Towel Supply | Akron | OH |
| Akron University | Akron | OH |
| Akron Water Works | Akron | OH |
| Akwell | Akron | OH |
| Akzo Chemical | Gallipolis | OH |
| Albert Bess | Hamilton | OH |
| Albert Kahn Associates | Sandusky | OH |
| Albert R. Hostetter | Dayton | OH |
| Albrecht Tool | Cleveland | OH |
| Alcoa | Chillicothe | OH |
| Alcoa | Barberton | OH |
| Alcoa | Cleveland | OH |
| Aldon Products | Cleveland | OH |
| Alexco | Niles | OH |
| Alfred A. Pope Building | Cleveland | OH |
| Alkali Rubber | Akron | OH |
| Allegheny Ludlum Steel | Waterville | OH |
| Allen County Institution Power Plant | Lima | OH |
| Allen Foundry & Machine | Lancaster | OH |
| Allen Packing | Rocky River | OH |
| Allen Products | Cleveland | OH |
| Allen Refractories | Canal Winchester | OH |
| Allen Refractories | Columbus | OH |
| Allen School | Canton | OH |
| Allen & Wheeler | Eldean | OH |
| Alliance Cold Storage & Packing | Alliance | OH |
| Alliance Defense Plant | Alliance | OH |
| Alliance Gas & Power | Alliance | OH |
| Alliance Research Center | Alliance | OH |
| Alliance Tubular Products | Alliance | OH |
| Allied Boiler | Cleveland | OH |
| Allied Chemical | Ironton | OH |
| Allied Chemical | South Point | OH |
| Allied Chemical | Toledo | OH |
| Allied Chemical | Youngstown | OH |
| Allied Chemical | Fostoria | OH |
| Allied Chemical | Painesville | OH |
| Allied Chemical | Warren | OH |
| Allied Chemical | Struthers | OH |
| Allied Egry Business Systems | Dayton | OH |
| Allied Engineering | Cleveland | OH |
