| 1976 | OPTIMUM INFOSOLUTIONS PRIVATE LIMITED - U72200RJ2001PTC017089 |
| 1977 | OPTIMUM INFOSYSTEMS PRIVATE LIMITED - U72200RJ2000PTC016232 |
| 1978 | OPTIMUM TECHSYS PRIVATE LIMITED - U72900RJ2014PTC044941 |
| 1979 | OPTRATEC TECHNOLOGIES PRIVATE LIMITED - U72900RJ2014PTC046499 |
| 1980 | ORANGE BPO SOLUTIONS PRIVATE LIMITED - U72200RJ2011PTC036409 |
| 1981 | ORANGE VOICE BPO PRIVATE LIMITED - U72900RJ2012PTC037943 |
| 1982 | ORCA WEB TECHNOLOGIES PRIVATE LIMITED - U72900RJ2012PTC038177 |
| 1983 | ORDENADOR COMMUNICATION PRIVATE LIMITED - U72900RJ2014PTC046204 |
| 1984 | ORGAMATION TECH PRIVATE LIMITED - U72900RJ2015PTC048234 |
| 1985 | ORIANA IT SOLUTIONS PRIVATE LIMITED - U72900RJ2014PTC045451 |
| 1986 | ORIGANO INFOSOLUTIONS PRIVATE LIMITED - U72200RJ2016PTC055428 |
| 1987 | ORINGIS TECHNOLOGIES PRIVATE LIMITED - U72200RJ2006PTC022413 |
| 1988 | ORION ITECH SOLUTIONS PRIVATE LIMITED - U72900RJ2014PTC045503 |
| 1989 | ORRLAB ANALYTICS PRIVATE LIMITED - U72900RJ2014PTC046762 |
| 1990 | ORTECH TECHNOLOGY PRIVATE LIMITED - U72900RJ2012PTC040722 |
| 1991 | ORYX TECHNOLOGIES PRIVATE LIMITED - U72900RJ2009PTC030014 |
| 1992 | OSCORP WORLDWIDE NETWORK PRIVATE LIMITED - U72900RJ2014PTC046268 |
| 1993 | OSHANO MARKETING PRIVATE LIMITED - U72501RJ2010PTC033101 |
| 1994 | OSHNIF TECHNOLOGIES PRIVATE LIMITED - U72900RJ2012PTC039862 |
| 1995 | OSMIC TECHNOLOGIES PRIVATE LIMITED - U72200RJ2010PTC033145 |
| 1996 | OSPHERE IT SOLUTIONS PRIVATE LIMITED - U72900RJ2012PTC039607 |
| 1997 | OURANOS SOLUTIONS (OPC) PRIVATE LIMITED - U72900RJ2017OPC057800 |
| 1998 | OURIOUS SOFTWARE PRIVATE LIMITED - U72200RJ2012PTC039276 |
| 1999 | OUTFACE TECHNOLOGIES PRIVATE LIMITED - U72200RJ2016PTC054821 |
| 2000 | OUTREACH INFOTECH PRIVATE LIMITED - U72200RJ2013PTC042743 |