Stockholders' Equity (Tables)
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12 Months Ended |
Dec. 31, 2016 |
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| Summary of Stock Options Activity |
The activity for stock options under the Company’s stock plans is as follows:
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Remaining
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weighted-
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Weighted-
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average
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Per share
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average
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contractual
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average
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Price per
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exercise
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terms
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intrinsic
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Options
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share
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price
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(in years)
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value
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Outstanding as of December 31, 2013
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2,328,675
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$0.60-$8.70
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$
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1.94
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7.04
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$
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10.23
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Granted
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754,916
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16.62-24.52
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17.81
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Exercised
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(736,519
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)
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0.60-16.62
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1.28
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Forfeited
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(80,640
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)
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0.60-16.62
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5.81
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Expired
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(4,799
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0.60-8.37
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1.09
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Outstanding as of December 31, 2014
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2,261,633
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0.60-24.52
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7.31
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6.43
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24.06
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Vested and exercisable as of December 31, 2014
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1,100,539
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0.60-18.93
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2.02
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5.73
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29.35
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Vested and expected to vest as of December 31, 2014
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2,144,974
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0.60-24.52
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7.19
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6.38
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24.18
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Outstanding as of December 31, 2014
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2,261,633
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0.60-24.52
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7.31
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6.43
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24.06
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Granted
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759,301
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37.10-46.66
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39.91
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Exercised
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(676,715
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0.60-24.52
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2.39
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Forfeited
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(48,849
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0.75-38.54
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16.28
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Expired
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—
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—
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—
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Outstanding as of December 31, 2015
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2,295,370
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0.60-46.66
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19.36
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5.98
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21.07
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Vested and exercisable as of December 31, 2015
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933,707
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0.60-46.66
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7.16
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5.55
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32.97
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Vested and expected to vest as of December 31, 2015
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2,179,294
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0.60-46.66
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19.15
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5.96
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21.27
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Outstanding as of December 31, 2015
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2,295,370
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0.60-46.66
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19.36
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5.98
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21.07
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Granted
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683,998
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44.19-58.95
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44.70
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Exercised
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(570,079
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0.60-46.66
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12.32
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Forfeited
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(53,247
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1.17-44.19
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28.09
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Expired
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(515
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8.70
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8.70
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Outstanding as of December 31, 2016
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2,355,527
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0.60-58.95
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28.22
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5.42
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38.95
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Vested and exercisable as of December 31, 2016
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1,023,865
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0.60-46.66
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16.61
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4.96
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50.56
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Vested and expected to vest as of December 31, 2016
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2,259,811
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$0.60-$46.66
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$
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27.95
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5.40
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$
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39.22
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| Summary of Stock-based Compensation Expense |
Stock-based compensation expense recognized for the years ended December 31, 2016, 2015 and 2014 was as follows:
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Years ended December 31,
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(amounts in thousands)
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2016
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2015
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2014
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Stock-based compensation expense by type of award:
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Stock option plan awards
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$
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6,850
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$
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3,280
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$
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1,317
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Employee stock purchase plan
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444
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360
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134
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Total stock-based compensation expense
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$
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7,294
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$
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3,640
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$
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1,451
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For the years ended December 31, 2016, 2015 and 2014, stock-based compensation expense recognized under ASC 718, included in cost of revenues, sales and marketing expense, general and administrative expense, and research and development expense was as follows:
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Years ended December 31,
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(amounts in thousands)
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2016
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2015
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2014
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Cost of revenue
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$
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639
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$
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433
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$
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172
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Sales and marketing
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1,142
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1,009
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443
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General and administrative
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4,737
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1,767
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658
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Research and development
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776
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431
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178
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Total stock-based compensation expense
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$
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7,294
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$
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3,640
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$
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1,451
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| Assumptions Used to Estimate Fair Value of Employee Options |
The value of employee options was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions used:
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2016
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2015
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2014
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Expected term (years)
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3.54-5.48
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3.50-5.48
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4.02-6.99
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Risk free interest rate
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1.00-1.40%
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0.95-1.77%
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1.32-2.02%
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Expected dividend yield
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None
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None
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None
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Volatility
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43.95-45.93%
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41.99-44.87%
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42.15-52.73%
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| Reconciliation of Warrant Activity |
A reconciliation of warrant activity from January 1, 2015 to December 31, 2015 is as follows:
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Issued and
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Issued and
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outstanding
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outstanding
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warrants as of
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Warrants
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Warrants
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warrants as of
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January 1, 2015
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exercised
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expired
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December 31, 2015
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Common stock
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15,218
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15,218
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—
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—
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| Redeemable Convertible Preferred Stock |
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| Summary of Convertible Preferred Stock |
A summary of the terms of the various types of redeemable convertible preferred stock at December 31, 2013, is as follows:
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Series
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B
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C
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D
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E
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F
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G
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Total
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Shares authorized
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500,000
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400,000
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1,700,000
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1,700,000
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2,800,000
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2,900,000
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10,000,000
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Shares issued
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425,511
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365,903
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1,573,126
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1,634,874
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2,701,957
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2,840,260
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9,541,631
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Par value
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$
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0.001
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$
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0.001
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$
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0.001
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$
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0.001
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$
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0.001
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$
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0.001
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Conversion rate
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1.45108
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1.73014
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1.87951
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2.69244
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1.00000
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1.00000
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Liquidation preference per
share
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$
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11.880
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$
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17.580
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$
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21.900
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$
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19.224
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$
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7.140
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$
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14.083
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Dividend rate
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5
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%
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8
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%
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8
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%
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8
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%
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8
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%
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8
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%
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July
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October
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February
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June
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2005 to
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2007 to
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2010 to
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March
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Issue date
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July 2003
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2004
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July 2007
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February 2009
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June 2010
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2012
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Redemption date
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January 1,
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January 1,
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January 1,
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January 1,
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January 1,
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January 1,
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2016
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2016
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2016
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2016
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2016
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2016
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| Nonredeemable Convertible Preferred Stock |
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| Summary of Convertible Preferred Stock |
A summary of the terms of non-redeemable convertible preferred stock at December 31, 2013 is as follows:
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Series A
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Shares authorized
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100,000
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Share issued
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66,666
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Par value
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$
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0.001
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Conversion rate
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1.01706
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Liquidation preference per share
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$
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3.750
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Dividend rate
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5
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%
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Issue date
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May 2002
|
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|