Game |
| Result | Moves |
Year | Event/Locale | Opening |
51. R Costigan vs W J Donaldson |
| 0-1 | 67 | 2005 | USCL San Francisco vs Philadelphia | D02 Queen's Pawn Game |
52. R Costigan vs J Friedel |
| 1-0 | 88 | 2005 | USCL Boston vs Philadelphia | D02 Queen's Pawn Game |
53. J Bonin vs R Costigan |
 | 1-0 | 32 | 2005 | USCL Philadelphia vs New York | D00 Queen's Pawn Game |
54. Browne vs R Costigan |
 | 1-0 | 39 | 2006 | 34th World Open | C98 Ruy Lopez, Closed, Chigorin |
55. R Costigan vs M Gagunashvili |
| 0-1 | 35 | 2006 | 34th World Open | A45 Queen's Pawn Game |
56. P Charbonneau vs R Costigan |
| 0-1 | 45 | 2006 | US Chess League | C91 Ruy Lopez, Closed |
57. R Costigan vs I Foygel |
| 0-1 | 45 | 2006 | US Chess League | B07 Pirc |
58. R Costigan vs J Friedel |
| ½-½ | 79 | 2006 | US Chess League | C49 Four Knights |
59. R Costigan vs S Winer |
| 1-0 | 27 | 2006 | US Chess League | B40 Sicilian |
60. R Costigan vs C Jones |
| ½-½ | 53 | 2006 | USA tt | D73 Neo-Grunfeld, 5.Nf3 |
61. T Enkhbat vs R Costigan |
| 1-0 | 52 | 2007 | USA tt | A44 Old Benoni Defense |
62. Lenderman vs R Costigan |
| 1-0 | 30 | 2008 | United States Chess League | D15 Queen's Gambit Declined Slav |
63. R Costigan vs Shankland |
 | 0-1 | 45 | 2008 | United States Chess League | C00 French Defense |
64. R Costigan vs D Ippolito |
| ½-½ | 68 | 2008 | United States Chess League | B40 Sicilian |
65. D Shmelov vs R Costigan |
| ½-½ | 49 | 2008 | United States Chess League | A59 Benko Gambit |
66. R Costigan vs Z Bayaraa |
| ½-½ | 144 | 2008 | US Chess League | A46 Queen's Pawn Game |
67. R Costigan vs J Bonin |
| ½-½ | 35 | 2008 | US Chess League | A43 Old Benoni |
68. R Costigan vs M Esserman |
| 0-1 | 29 | 2008 | US Chess League | A80 Dutch |
69. R Costigan vs R Zimmer |
| 0-1 | 51 | 2009 | USCL | B08 Pirc, Classical |
70. K Troff vs R Costigan |
| 1-0 | 40 | 2017 | PRO Chess League (Pacific) | A44 Old Benoni Defense |
71. R Costigan vs T Gareyev |
| 0-1 | 54 | 2017 | PRO Chess League (Pacific) | A46 Queen's Pawn Game |