| 1 | PNTX | Great Lakes Chemical Corp., Specialty Chemicals | added 10/1995; 7/2000-7/2005; added 10/2007 | | NAKINA |
| 2 | PNTX | QO Chemicals, Inc. | 1/1994; eliminated 10/1995 | | NAKINA |
| 3 | PNTX | Putnam Tank Car Corp. | added 7/1972; 1/1975-1/1980; eliminated 1/1982 | | NAKINA |
| 4 | PNTX | Putnam Tank Car Corp. | 1/75-1/80; eliminated 1/82 | | NRHS |
| 5 | PNTX | QO Chemicals, Inc. | 1/94; eliminated 10/95 | | NRHS |
| 6 | PNTX | Great Lakes Chemical Corp., Specialty Chemicals | added 10/95; 7/2000 | | NRHS |
| 7 | PNTX | *PUTMAN TANK CAR CORP. | | | PWRC |
| 8 | PNTX | +GREAT LAKES CHEMICAL CORP - SPECIALITY CHEMICALS [QO CHEMICALS, INC.] | | | PWRC |
| 9 | PNTX | Great Lakes Chemical Corporation Specialty Chemicals | | | RSRV |
| 10 | PNTX | QO CHEMICALS, INC. | | | SCAC4 |
