v3.19.3.a.u2

Stockholders' Equity (Tables) | 12 Months Ended
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Dec. 31, 2019
Schedule of Reserved Shares of Common Stock for Issuance | At December 31, 2019, the Company had reserved shares of common stock for issuance as follows (in thousands):
|  | As of December 31, 2019 |
Common stock awards granted under equity incentive plans |  |  | 15,668 |
Common stock awards available for issuance under the 2017 Employee Stock Purchase Plan * |  |  | 2,089 |
Common stock awards available for issuance under the 2017 Equity Incentive Plan |  |  | 16,950 |
Total reserved shares of common stock |  |  | 34,707 |
Summary of Restricted Stock Unit Activity | Restricted stock unit activity for the year ended December 31, 2019 is as follows (in thousands, except per share data):
|  | Number of Shares |  |  | Weighted Average Grant Date Fair Value Per Share |
Balance, December 31, 2018 |  |  | 3,686 |  |  | $ | 48.50 |
Awarded |  |  | 2,228 |  |  |  | 87.60 |
Released |  |  | (822 | ) |  |  | 49.26 |
Forfeited |  |  | (548 | ) |  |  | 50.40 |
Balance, December 31, 2019 - outstanding |  |  | 4,544 |  |  | $ | 67.30 |
Schedule of Stock Option Activity | The following table summarizes the Company’s stock option activities under the 2008 Plan and 2017 Plan (in thousands, except per share data):
|  | Number of Shares |  |  | Weighted Average Exercise Price |  |  | Weighted Average Remaining Contractual Life (Years) |  |  | Weighted Average Grant Date Fair Value Per Share |  |  | Aggregate Intrinsic Value |
Balance, December 31, 2018 |  |  | 16,371 |  |  | $ | 8.59 |  |  |  | 6.8 |  |  |  | — |  |  |  |  |
Granted |  |  | 572 |  |  |  | 100.06 |  |  |  | — |  |  | $ | 39.23 |  |  |  |  |
Exercised |  |  | (5,352 | ) |  |  | 5.35 |  |  |  | — |  |  |  | — |  |  |  |  |
Forfeited and expired |  |  | (467 | ) |  |  | 8.77 |  |  |  | — |  |  |  | — |  |  |  |  |
Balance, December 31, 2019 - outstanding |  |  | 11,124 |  |  | $ | 14.84 |  |  |  | 6.2 |  |  |  | — |  |  | $ | 1,324,461 |
Options exercisable at December 31, 2019 |  |  | 6,603 |  |  | $ | 5.84 |  |  |  | 5.1 |  |  |  | — |  |  | $ | 845,590 |
Schedule of Share-based Compensation Expense Included in Consolidated Statements of Operations | The following table shows total stock-based compensation expense included in the accompanying Consolidated Statements of Operations for the years ended December 31, 2019, 2018 and 2017 (in thousands):
|  | Years Ended December 31, |
|  | 2019 |  |  | 2018 |  |  | 2017 |
Cost of platform revenue |  | $ | 342 |  |  | $ | 97 |  |  | $ | 81 |
Cost of player revenue |  |  | 1,072 |  |  |  | 469 |  |  |  | 145 |
Research and development |  |  | 40,036 |  |  |  | 18,538 |  |  |  | 4,714 |
Sales and marketing |  |  | 24,179 |  |  |  | 10,459 |  |  |  | 2,817 |
General and administrative |  |  | 19,546 |  |  |  | 8,111 |  |  |  | 3,196 |
Total stock-based compensation |  | $ | 85,175 |  |  | $ | 37,674 |  |  | $ | 10,953 |
Summary of Assumptions Used to Value Stock-Based Awards Granted | The assumptions used to value stock-based awards granted during the years ended December 31, 2019, 2018 and 2017 are as follows:
|  | Years Ended December 31, |
|  | 2019 |  |  | 2018 |  |  | 2017 |
Dividend rate |  |  | — |  |  |  | — |  |  |  | — |
Expected term (in years) |  | 5.0 - 6.7 |  |  | 5.3 - 6.8 |  |  | 5.3 - 6.5 |
Risk-free interest rate |  | 1.35 - 2.56% |  |  | 2.32 - 2.88% |  |  | 1.87 - 2.25% |
Expected volatility |  | 35 - 36% |  |  | 38 - 40% |  |  | 39 - 44% |
Fair value of common stock |  |  | — |  |  |  | — |  |  | $2.56 - $18.46 |
Convertible Preferred Stock Warrants |
Summary of Assumptions Used to Value Stock-Based Awards Granted | The Company valued the convertible preferred stock warrants using the following assumptions:
|  | Year Ended |
|  | December 31, 2017 |
Dividend rate |  |  | — |
Expected term (in years) |  | 3.0 - 9.7 |
Risk-free interest rate |  | 1.5 - 2.3% |
Expected volatility |  | 44 - 51% |

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