| 1 | A a a Leasing, Inc.Not reported | Corporation | Not reported | Not reported |
| 2 | A & D Plumbing & Heating, Inc.Not reported | Corporation | Not reported | Not reported |
| 3 | A & R Dairy & Delicatessen IncNot reported | Corporation | Not reported | Not reported |
| 4 | A-z, Inc.Not reported | Corporation | Not reported | Not reported |
| 5 | Abmar Developers, Inc.Not reported | Corporation | Not reported | Not reported |
| 6 | Ackerman's Serv-all IncNot reported | Corporation | Not reported | Not reported |
| 7 | Liberty Brick and Block, Inc.Not reported | Corporation | Not reported | Not reported |
| 8 | Ad-bench Service, Inc.Not reported | Corporation | Not reported | Not reported |
| 9 | Greater Allegheny Education FoundationNot reported | Nonprofit | Not reported | Not reported |
| 10 | Aerotube Wing AssociatesNot reported | Nonprofit | Not reported | Not reported |
| 11 | Airco Financial Services, Inc.Not reported | Corporation | Not reported | Not reported |
| 12 | Checker Service CompanyNot reported | Corporation | Not reported | Not reported |
| 13 | Al-burt Apartments CorporationNot reported | Corporation | Not reported | Not reported |
| 14 | Albee Leasing CompanyNot reported | Corporation | Not reported | Not reported |
| 15 | Algen Corp.Not reported | Corporation | Not reported | Not reported |
| 16 | Algonac Hunting and Fishing ClubNot reported | Nonprofit | Not reported | Not reported |
| 17 | Aliquippa Boosters AssociationNot reported | Nonprofit | Not reported | Not reported |
| 18 | All Weather Service, Inc.Not reported | Corporation | Not reported | Not reported |
| 19 | Allegheny Beer Distributing CoNot reported | Corporation | Not reported | Not reported |
| 20 | Allegheny Beverage Co., Inc.Not reported | Corporation | Not reported | Not reported |
| 21 | Allegheny County Chevrolet Dealers Advertising Association, Inc.Not reported | Corporation | Not reported | Not reported |
| 22 | Allegheny County Council of Senior CitizensNot reported | Nonprofit | Not reported | Not reported |
| 23 | Allegheny County Midget LeagueNot reported | Nonprofit | Not reported | Not reported |
| 24 | Allegheny Insurance Agency, Inc.Not reported | Corporation | Not reported | Not reported |
| 25 | Alpine Hotel IncNot reported | Corporation | Not reported | Not reported |
| 26 | Alstan Inc. of Mc KeesportNot reported | Corporation | Not reported | Not reported |
| 27 | Alstan Manufacturing CoNot reported | Corporation | Not reported | Not reported |
| 28 | Tygart Industries Inc.Not reported | Corporation | Not reported | Not reported |
| 29 | American Brake Centers, Inc.Not reported | Corporation | Not reported | Not reported |
| 30 | American Croation Catholic Youth CenterNot reported | Nonprofit | Not reported | Not reported |
| 31 | American Nationality Heritage FoundationNot reported | Nonprofit | Not reported | Not reported |
| 32 | American Torch Tip CompanyNot reported | Corporation | Not reported | Not reported |
| 33 | Jack Mooney Vending CompanyNot reported | Corporation | Not reported | Not reported |
| 34 | Amper Steel CorporationNot reported | Corporation | Not reported | Not reported |
| 35 | Amper, Thomas Co IncNot reported | Corporation | Not reported | Not reported |
| 36 | Anderson Motors Inc.Not reported | Corporation | Not reported | Not reported |
| 37 | Angel Sales Inc.Not reported | Corporation | Not reported | Not reported |
| 38 | Answer-phone, Inc.Not reported | Corporation | Not reported | Not reported |
| 39 | Antonelli Land CompanyNot reported | Corporation | Not reported | Not reported |
| 40 | Appalachian Constructors IncorporatedNot reported | Corporation | Not reported | Not reported |
| 41 | Auxiliary Police Association of MckeesportNot reported | Nonprofit | Not reported | Not reported |
| 42 | Auxiliary Police of Liberty BoroughNot reported | Nonprofit | Not reported | Not reported |
| 43 | The Avag CompanyNot reported | Corporation | Not reported | Not reported |
| 44 | Avant Garde, Inc.Not reported | Corporation | Not reported | Not reported |
| 45 | Ashar Automotive, Inc.Not reported | Corporation | Not reported | Not reported |
| 46 | Associated Craftsmen, Inc.Not reported | Corporation | Not reported | Not reported |
| 47 | Associated Drug IncNot reported | Corporation | Not reported | Not reported |
| 48 | Pauline Auberle FoundationNot reported | Nonprofit | Not reported | Not reported |
| 49 | Audrey-phillips Shops IncNot reported | Corporation | Not reported | Not reported |
| 50 | Authentic Homes, Inc.Not reported | Corporation | Not reported | Not reported |