|  |
|--|
|  |
|  |

|                                       |
|---------------------------------------|
|                                       |
| Investor Contact:                     |
| Tom Line-Chief Financial Officer      |
| 614-255-5989 (tline@diamond-hill.com) |

|                                                         |
|---------------------------------------------------------|
|                                                         |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
|                                                    | Three Months Ended  December 31, |   |   |   | Year EndedDecember 31, |   |   |
|                                                    | 2017 |   | 2016 |   | % Change |   | 2017 |   | 2016 |   | % Change |
| Revenues:                                               |   |   |   |   |   |   |  |   |   |   |   |
|     Investment advisory(a)          | $ | 34,487 |  |   | $ | 36,893 |  |   | (7)% |   | $ | 132,689 |  |   | $ | 121,645 |  |   | 9% |
|     Mutual fund administration, net | 3,266 |  |   | 3,146 |  |   | 4% |   | 12,513 |  |   | 14,458 |  |   | (13)% |
|     Total revenue                   | 37,753 |  |   | 40,039 |  |   | (6)% |   | 145,202 |  |   | 136,103 |  |   | 7% |
|                                                    |   |   |   |   |   |   |   |   |   |   |   |
| Operating expenses                                      | 19,443 |  |   | 20,512 |  |   | (5)% |   | 78,200 |  |   | 73,034 |  |   | 7% |
| Net operating income                                    | 18,310 |  |   | 19,527 |  |   | (6)% |   | 67,002 |  |   | 63,069 |  |   | 6% |
|                                                    |  |   |   |   |   |   |   |   |   |   |   |
| Investment income (loss), net                           | 4,439 |  |   | 2,522 |  |   |   |   | 14,017 |  |   | 7,517 |  |   |   |
| Gain on sale of subsidiary                              | — |  |   | — |  |   |   |   | — |  |   | 2,676 |  |   |   |
|                                                    |   |   |   |   |   |   |   |   |   |   |   |
| Income before taxes                                     | 22,749 |  |   | 22,049 |  |   | 3% |   | 81,019 |  |   | 73,262 |  |   | 11% |
|                                                    |   |   |   |   |   |   |   |   |   |   |   |
| Income tax provision                                    | (10,398 | ) |   | (8,171 | ) |   | 27% |   | (29,417 | ) |   | (26,668 | ) |   | 10% |
| Net income attributable to common shareholders          | $ | 11,895 |  |   | $ | 13,645 |  |   | (13)% |   | $ | 49,989 |  |   | $ | 46,052 |  |   | 9% |
|                                                    |   |   |   |   |   |   |   |   |   |   |   |
| Earnings per share - diluted                            | $ | 3.43 |  |   | $ | 3.99 |  |   | (14)% |   | $ | 14.48 |  |   | $ | 13.49 |  |   | 7% |
| Operating profit margin                                 | 49 | % |   | 49 | % |   |   |   | 46 | % |   | 46 | % |   |   |

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|                                                                   |
|-------------------------------------------------------------------|
|                                                                   |  |  |  |  |  |  |  |
|                                                              | December 31, |
|                                                              | 2017 |   | 2016 |
| Assets                                                            |   |   |   |
|     Cash equivalents and investment portfolio | $ | 215,078 |  |   | $ | 165,206 |  |
|     Accounts receivable                       | 19,220 |  |   | 18,605 |  |
|     Deferred taxes                            | 5,844 |  |   | 8,737 |  |
|     Other assets                              | 10,246 |  |   | 7,170 |  |
|     Total assets                              | $ | 250,388 |  |   | $ | 199,718 |  |
|                                                              |   |   |   |
| Liabilities                                                       | 57,868 |  |   | 46,653 |  |
|                                                              |   |   |   |
| Redeemable noncontrolling interest                                | 20,077 |  |   | 13,841 |  |
|                                                              |   |   |   |
| Total shareholders' equity                                        | 172,443 |  |   | 139,224 |  |
|                                                              |   |   |   |
| Total liabilities and shareholders' equity                        | $ | 250,388 |  |   | $ | 199,718 |  |
|                                                              |   |   |   |
| Book value per share                                              | $ | 49.69 |  |   | $ | 40.81 |  |
| Outstanding shares                                                | 3,470 |  |   | 3,412 |  |

|                                                |
|------------------------------------------------|
|                                                |  |  |  |  |  |  |  |
|                                           | Change in Assets Under Management |
|                                           | For the Year Ended December 31, |
| (in millions)                                  | 2017 |   | 2016 |
| AUM at beginning of the year                   | $ | 19,381 |  |   | $ | 16,841 |  |
| Net cash inflows (outflows)                    |   |   |   |
|     proprietary funds      | 843 |  |   | 548 |  |
|     sub-advised funds      | (164 | ) |   | 639 |  |
|     institutional accounts | (254 | ) |   | (1,023 | ) |
|                                           | 425 |  |   | 164 |  |
| Net market appreciation and income             | 2,511 |  |   | 2,376 |  |
| Increase during the year                       | 2,936 |  |   | 2,540 |  |
| AUM at end of the year                         | $ | 22,317 |  |   | $ | 19,381 |  |

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|                                                                                                     |
|-----------------------------------------------------------------------------------------------------|
|                                                                                                     |  |  |  |  |  |  |  |
|                                                                                                |  Year Ended December 31, |
|  (in thousands, except per share data)                                                         | 2017 |   | 2016 |
| Total revenue                                                                                       | $ | 145,202 |  |   | $ | 136,103 |  |
|                                                                                                |   |   |   |
| Net operating income, GAAP basis                                                                    | $ | 67,001 |  |   | $ | 63,069 |  |
|  Non-GAAP adjustment:                                                                          |   |   |   |
|      Gains (losses) on deferred compensation plan investments, net(1)      | 2,382 |  |   | 1,837 |  |
| Net operating income, as adjusted, non-GAAP basis(2)                                                | 69,383 |  |   | 64,906 |  |
|  Non-GAAP Adjustment:                                                                          |   |   |   |
|      Tax provision on net operating income, as adjusted, non-GAAP basis(3) | (25,192 | ) |   | (23,626 | ) |
| Net operating income, as adjusted, after tax, non-GAAP basis(4)                                     | $ | 44,191 |  |   | $ | 41,280 |  |
|                                                                                                |   |   |   |
| Net operating income, as adjusted after tax per diluted share, non-GAAP basis(5)                    | $ | 12.80 |  |   | $ | 12.09 |  |
| Diluted weighted average shares outstanding, GAAP basis                                             | 3,452 |  |   | 3,413 |  |
|                                                                                                |   |   |   |
| Operating profit margin, GAAP basis                                                                 | 46 | % |   | 46 | % |
| Operating profit margin, as adjusted, non-GAAP basis(6)                                             | 48 | % |   | 48 | % |

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