|
Equity Compensation (Tables)
|
12 Months Ended |
|
Dec. 31, 2014
|
| Equity Compensation |
|
| Summary of stock option activity |
|
|
|
Shares Subject
to Options
Outstanding
|
|
Weighted
Average
Grant Date
Fair Value
|
|
Weighted
Average
Exercise Price
|
|
Weighted
Average
Remaining
Contractual
Life (Years)
|
|
|
Balance at December 31, 2012
|
|
4,649,238
|
|
|
|
$
|
5.56
|
|
|
|
|
Granted
|
|
480,698
|
|
$
|
10.08
|
|
13.20
|
|
|
|
|
Exercised
|
|
(107,042
|
)
|
|
|
4.17
|
|
|
|
|
Expired
|
|
(27,772
|
)
|
|
|
5.79
|
|
|
|
|
Forfeited
|
|
(89,908
|
)
|
|
|
7.14
|
|
|
|
|
Balance at December 31, 2013
|
|
4,905,214
|
|
|
|
6.31
|
|
|
|
|
Granted
|
|
1,592,268
|
|
9.99
|
|
18.00
|
|
|
|
|
Exercised
|
|
(1,512,514
|
)
|
|
|
4.24
|
|
|
|
|
Expired
|
|
(136
|
)
|
|
|
7.40
|
|
|
|
|
Forfeited
|
|
(133,611
|
)
|
|
|
13.77
|
|
|
|
|
Balance at December 31, 2014
|
|
4,851,221
|
|
|
|
10.57
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Exercisable options at December 31, 2013
|
|
3,285,695
|
|
|
|
4.88
|
|
4.9
|
|
|
Vested and expected to vest at December 31, 2013
|
|
4,544,942
|
|
|
|
6.15
|
|
5.9
|
|
|
Exercisable options at December 31, 2014
|
|
2,494,711
|
|
|
|
6.33
|
|
5.6
|
|
|
Vested and expected to vest at December 31, 2014
|
|
4,615,485
|
|
|
|
10.30
|
|
7.0
|
|
|
| Summary of stock options outstanding and exercisable |
The following table summarizes information about stock options outstanding and exercisable at December 31, 2014:
|
|
|
Options Outstanding
|
|
Options Exercisable
|
|
|
Range of Exercise Prices
|
|
Weighted
Average
Exercise
Price
|
|
Number of
Underlying
Shares
|
|
Weighted-
Average
Remaining
Contractual
Life (in
years)
|
|
Number of
Underlying
Shares
|
|
Weighted-
Average
Remaining
Contractual
Life (in
years)
|
|
|
$0.78 - 1.72
|
|
$
|
1.10
|
|
37,399
|
|
0.8
|
|
37,399
|
|
0.8
|
|
|
1.97 - 3.38
|
|
2.57
|
|
248,746
|
|
1.9
|
|
248,746
|
|
1.9
|
|
|
3.58 - 6.14
|
|
5.64
|
|
1,570,282
|
|
5.7
|
|
1,416,661
|
|
5.6
|
|
|
6.34 - 9.94
|
|
8.27
|
|
1,007,227
|
|
7.2
|
|
627,128
|
|
7.1
|
|
|
11.28 - 16.97
|
|
13.94
|
|
1,180,368
|
|
9.0
|
|
143,901
|
|
6.3
|
|
|
17.66 - 22.92
|
|
21.00
|
|
807,199
|
|
9.1
|
|
20,876
|
|
8.1
|
|
|
|
|
|
|
4,851,221
|
|
|
|
2,494,711
|
|
|
|
|
| Summary of aggregate intrinsic-value of options exercised, exercisable, and vested and expected to vest |
The following table summarizes the aggregate intrinsic-value of options exercised, outstanding and exercisable (in thousands):
|
|
|
For the Years Ended and as of
December 31,
|
|
|
|
|
2012
|
|
2013
|
|
2014
|
|
|
Options Exercised
|
|
$
|
1,310
|
|
$
|
1,315
|
|
$
|
22,668
|
|
|
Options Exercisable
|
|
16,800
|
|
42,116
|
|
22,718
|
|
|
Options Vested and Expected to Vest
|
|
25,773
|
|
55,099
|
|
27,663
|
|
|
| Schedule of assumptions used to estimate fair value of option awards |
|
|
|
Years Ended December 31,
|
|
|
|
|
2012
|
|
2013
|
|
2014
|
|
|
Expected volatility
|
|
59 - 63%
|
|
56 - 59%
|
|
49 - 60%
|
|
|
Expected dividends
|
|
0%
|
|
0%
|
|
0%
|
|
|
Expected terms (in years)
|
|
5.0 - 6.1
|
|
3.3 - 7.2
|
|
1.0 - 6.1
|
|
|
Risk-free rate
|
|
0.7 - 1.0%
|
|
0.8 - 1.7%
|
|
0.3 - 2.0%
|
|
|
| Schedule of total stock-based compensation expense classified in statements of operations |
Total stock-based compensation expense has been classified as follows in the accompanying statements of operations (in thousands):
|
|
|
Years Ended December 31,
|
|
|
|
|
2012
|
|
2013
|
|
2014
|
|
|
Cost of revenue
|
|
$
|
78
|
|
$
|
63
|
|
$
|
105
|
|
|
Research and development
|
|
704
|
|
1,414
|
|
2,235
|
|
|
Sales and marketing
|
|
580
|
|
743
|
|
1,110
|
|
|
General and administrative
|
|
1,507
|
|
1,540
|
|
1,891
|
|
|
Total stock-based compensation expense
|
|
$
|
2,869
|
|
$
|
3,760
|
|
$
|
5,341
|
|
|