| Game |
| Result | Moves |
Year | Event/Locale | Opening |
| 1. de Firmian vs Seirawan |
| 0-1 | 38 | 1981 | Lone Pine Open | B18 Caro-Kann, Classical |
| 2. de Firmian vs T de Jong |
| 1-0 | 30 | 1982 | 6th Lloyds Bank Masters Open | B18 Caro-Kann, Classical |
| 3. de Firmian vs Seirawan |
 | 1-0 | 40 | 1984 | United States Championship | B18 Caro-Kann, Classical |
| 4. de Firmian vs R Behling |
| 1-0 | 42 | 1984 | 8th Lloyds Bank Masters Open | B18 Caro-Kann, Classical |
| 5. de Firmian vs Miles |
| ½-½ | 54 | 1985 | Tunis Interzonal | B18 Caro-Kann, Classical |
| 6. de Firmian vs Miles |
| 0-1 | 50 | 1987 | 15th World Open | B18 Caro-Kann, Classical |
| 7. de Firmian vs Adianto |
| 0-1 | 36 | 1987 | Pan Pacific International | B18 Caro-Kann, Classical |
| 8. de Firmian vs Korchnoi |
| 0-1 | 34 | 1989 | Lugano Open | B18 Caro-Kann, Classical |
| 9. de Firmian vs Miles |
| ½-½ | 53 | 1989 | Biel | B18 Caro-Kann, Classical |
| 10. de Firmian vs E Schiller |
| 1-0 | 44 | 1993 | 21st World Open | B18 Caro-Kann, Classical |
| 11. de Firmian vs H Danielsen |
| ½-½ | 51 | 1993 | Farum Open | B18 Caro-Kann, Classical |
| 12. de Firmian vs M Morris |
| 1-0 | 41 | 1995 | Chicago op | B18 Caro-Kann, Classical |
| 13. de Firmian vs L Brunner |
| 1-0 | 35 | 1995 | Biel | B18 Caro-Kann, Classical |
| 14. de Firmian vs A Lesiege |
| ½-½ | 42 | 1997 | Bermuda GM | B18 Caro-Kann, Classical |
| 15. de Firmian vs Dautov |
| ½-½ | 46 | 1999 | Julian Borowski 1st | B18 Caro-Kann, Classical |
| 16. de Firmian vs Fridman |
| ½-½ | 48 | 1999 | Julian Borowski 1st | B18 Caro-Kann, Classical |
| 17. de Firmian vs A Ivanov |
| 0-1 | 54 | 2000 | United States Championship | B18 Caro-Kann, Classical |
| 18. de Firmian vs Yermolinsky |
| 1-0 | 59 | 2002 | United States Championship | B18 Caro-Kann, Classical |
| 19. de Firmian vs S G Jensen |
| 1-0 | 38 | 2004 | Copenhagen AS04 Centenary | B18 Caro-Kann, Classical |
| 20. de Firmian vs E Hermansson |
| 1-0 | 43 | 2005 | Rilton Cup 34th | B18 Caro-Kann, Classical |
| 21. de Firmian vs Yudasin |
| ½-½ | 35 | 2005 | Marshall Chess Club Championship | B18 Caro-Kann, Classical |
| 22. de Firmian vs E Thingstad |
| 0-1 | 48 | 2007 | Arctic Chess Challenge | B18 Caro-Kann, Classical |
| 23. de Firmian vs M Mchedlishvili |
| ½-½ | 17 | 2009 | Gjovik Open-A 2008/09 | B18 Caro-Kann, Classical |
| 24. de Firmian vs Shankland |
| ½-½ | 62 | 2012 | Imre Koenig Memorial Rapid | B18 Caro-Kann, Classical |
Kibitzing
