Note 11. Stock-Based Compensation

2015 Equity Incentive Plan

In January 2015, our board of directors adopted our 2015 Equity Incentive Plan (2015 Plan), which became effective prior to the completion of our IPO. A total of 12,200,000 shares of Class A common stock was initially reserved for issuance pursuant to future awards under our 2015 Plan. The number of shares of our Class A common stock available for issuance under our 2015 Plan will be increased on the first day of each fiscal year, with such increase equal to the lesser of: (i) 12,200,000 shares; (ii) 5% of the outstanding shares of our capital stock as of the last day of our immediately preceding fiscal year; or (iii) such other amount as our board of directors may determine. Additionally, any shares subject to outstanding awards under our 2006 Equity Incentive Plan (2006 Plan) or 2011 Equity Incentive Plan (2011 Plan) that are cancelled or repurchased subsequent to our 2015 Plan’s effective date will be returned to the pool of shares reserved for issuance under our 2015 Plan. Awards granted under our 2015 Plan may be (i) incentive stock options, (ii) nonstatutory stock options, (iii) restricted stock units, (iv) restricted stock awards or (v) stock appreciation rights, as determined by our board of directors at the time of grant. Options and restricted stock units generally vest 25% one year from the vesting commencement date and (a) in the case of options, 1/48th per month thereafter, and (b) in the case of restricted stock units, 1/16th per quarter thereafter. As of January 31, 2016, 13,777,992 shares are reserved for future issuance under our 2015 Plan.

2015 Employee Stock Purchase Plan

In January 2015, our board of directors adopted our 2015 Employee Stock Purchase Plan (2015 ESPP), which became effective prior to the completion of our IPO. A total of 2,500,000 shares of Class A common stock was initially reserved for issuance under our 2015 ESPP. The number of shares of our Class A common stock available for issuance under our ESPP will be increased on the first day of each fiscal year beginning in fiscal 2016, with such increase equal to the least of: (i) 2,500,000 shares; (ii) 1% of the outstanding shares of our capital stock on the first day of such fiscal year; or (iii) such other amount as our board of directors may determine. Our 2015 ESPP allows eligible employees to purchase shares of our Class A common stock at a discount of up to 15% of their eligible compensation through payroll deductions, subject to any plan limitations. Except for the initial offering period, our 2015 ESPP provides for 24-month offering periods beginning March 16 and September 16 of each year, and each offering period will consist of four six-month purchase periods.

On each purchase date, eligible employees will purchase our stock at a price per share equal to 85% of the lesser of (1) the fair market value of our stock on the offering date or (2) the fair market value of our stock on the purchase date. Our 2015 ESPP also has a feature whereby the offering period resets for a new 24 months if the fair value of our common stock on the last day of any purchase period is less than the original offering price. As of January 31, 2016, 2,761,742 shares are reserved for future issuance under our 2015 ESPP.

Early Exercises of Stock Options

Prior to our IPO, certain employees and directors exercised stock options prior to vesting with the approval of our board of directors. The unvested shares are subject to a repurchase right held by us at the original purchase price. Early exercises of options are not deemed to be substantive exercises for accounting purposes, and accordingly, amounts received for early exercises are initially recorded in other liabilities and are reclassified to common stock and additional paid-in capital as the underlying shares vest. As of January 31, 2016 and 2015, we had $11,000 and $286,000, respectively, in liabilities and 9,375 and 113,541 unvested shares, respectively, subject to repurchase related to early exercises of stock options.

Stock Options

The following table summarizes the stock option activity under the equity incentive plans and related information:

	Shares Subject to Options Outstanding					Weighted-Average
	Shares Subject to			Weighted-		Remaining
	Outstanding			Average Exercise		Contractual Life		Aggregate
	Options			Price		(Years)		Intrinsic Value
								(in thousands)
Balance as of January 31, 2014		18,427,075		$	3.65		8.45	$	191,809
Options granted		2,918,632			15.73
Option exercised		(2,306,816	)		2.61
Options forfeited/cancelled		(1,573,320	)		5.22
Balance as of January 31, 2015		17,465,571		$	5.67		7.80	$	229,713
Options granted		1,898,700			15.62
Option exercised		(2,196,516	)		3.26
Options forfeited/cancelled		(1,533,237	)		8.67
Balance as of January 31, 2016		15,634,518		$	6.92		7.12	$	82,541
Vested and expected to vest as of January 31, 2016		15,398,572		$	6.84		7.10	$	82,076
Exercisable as of January 31, 2016		9,587,096		$	4.14		6.42	$	68,926

The aggregate intrinsic value of options vested and expected to vest as of January 31, 2016 is calculated based on the difference between the exercise price and the current fair value of our common stock. The aggregate intrinsic value of exercised options for the years ended January 31, 2016, 2015 and 2014 was $24.8 million, $27.5 million and $17.8 million, respectively. The aggregate estimated fair value of stock options granted to employees that vested during the years ended January 31, 2016, 2015 and 2014 was $16.7 million, $16.4 million and $7.4 million, respectively. The weighted-average grant date fair value of options granted to employees during the years ended January 31, 2016, 2015 and 2014 was $6.72, $7.46 and $4.75 per share, respectively.

As of January 31, 2016, there was $29.2 million of unrecognized stock-based compensation expense related to outstanding stock options granted to employees that is expected to be recognized over a weighted-average period of 2.42 years.

Restricted Stock Units

The following table summarizes the restricted stock unit activity under the equity incentive plans and related information:

	Number of			Weighted-
	Restricted			Average
	Stock Units			Grant Date
	Outstanding			Fair Value
Unvested balance - January 31, 2014		225,300		$	14.06
Granted		5,091,479			15.77
Vested, net of shares withheld for employee payroll taxes		(37,991	)		14.53
Forfeited/cancelled, including shares withheld for employee payroll taxes		(339,079	)		16.42
Unvested balance - January 31, 2015		4,939,709		$	15.66
Granted		6,052,788			15.69
Vested, net of shares withheld for employee payroll taxes		(982,140	)		16.12
Forfeited/cancelled, including shares withheld for employee payroll taxes		(1,805,389	)		16.07
Unvested balance - January 31, 2016		8,204,968		$	15.54

As of January 31, 2016, there was $111.0 million of unrecognized stock-based compensation expense related to outstanding restricted stock units granted to employees that is expected to be recognized over a weighted-average period of 3.04 years.

Restricted Stock Awards

The following table summarizes the restricted stock awards activity under the equity incentive plans and related information:

	Number of			Weighted-
	Restricted			Average
	Stock			Grant Date
	Outstanding			Fair Value
Unvested balance - January 31, 2014		387,435		$	7.84
Granted		26,802			17.27
Vested, net of shares withheld for employee payroll taxes		(213,512	)		7.86
Forfeited/cancelled, including shares withheld for employee payroll taxes		(28,064	)		5.85
Unvested balance - January 31, 2015		172,661		$	9.60
Granted		28,864			17.54
Vested, net of shares withheld for employee payroll taxes		(102,619	)		11.79
Forfeited/cancelled, including shares withheld for employee payroll taxes		(68,299	)		8.87
Unvested balance - January 31, 2016		30,607		$	11.38

As of January 31, 2016, there was $123,000 of unrecognized stock-based compensation expense related to outstanding restricted stock awards under the equity incentive plans granted to employees that is expected to be recognized over a weighted-average period of 0.71 year.

In addition, in connection with our fiscal 2015 acquisitions, we issued 344,667 shares of restricted stock awards with a weighted-average grant date fair value of $12.96 per share. These restricted stock awards were separately authorized by our board of directors, and did not reduce the number of shares available for future issuance under our equity incentive plans.

As of January 31, 2016, there was $2.2 million of unrecognized stock-based compensation expense related to outstanding restricted stock awards granted outside of the equity incentive plans that is expected to be recognized over a weighted-average period of 1.62 years. In addition, there were 267,717 unvested shares as of January 31, 2016.

As of January 31, 2016, there was $0.7 million of unrecognized stock-based compensation related to 71,037 shares of contingently issuable common stock for certain bonus awards given in connection with our fiscal 2016 and 2015 acquisitions that is expected to be recognized over a weighted-average period of 1.41 years. In addition, there were 65,705 unvested shares as of January 31, 2016.

2015 ESPP

As of January 31, 2016, there was $11.8 million of unrecognized stock-based compensation expense related to our 2015 ESPP that is expected to be recognized over a weighted average period of 1.62 years.

Stock-Based Compensation

The following table summarizes the components of stock-based compensation expense recognized in the consolidated statements of operations (in thousands):

	Year Ended
	January 31,
	2016		2015		2014
Cost of revenue	$	4,664	$	1,492	$	450
Research and development		24,696		11,767		3,154
Sales and marketing		19,530		11,616		5,017
General and administrative		10,614		7,054		3,128
Total stock-based compensation	$	59,504	$	31,929	$	11,749

Determination of Fair Value

We estimated the fair value of employee stock options and ESPP purchase rights using a Black-Scholes option pricing model with the following assumptions:

	Year Ended
	January 31,
	2016						2015						2014
Employee Stock Options
Expected term (in years)		5.5		–	6.1			5.7		–	6.2			4.9		–	6.3
Risk-free interest rate		1.5	%	–	1.9	%		1.8	%	–	2.1	%		0.8	%	–	1.9	%
Volatility		42	%	–	44	%		45	%	–	49	%		48	%	–	57	%
Dividend yield					0	%					0	%					0	%
Employee Stock Purchase Plan
Expected term (in years)	0.5			–	2.0			0.6		–	2.1						—
Risk-free interest rate		0.2	%	–	0.8	%		0.1	%	–	0.6	%					—
Volatility		33	%	–	41	%		37	%	–	41	%					—
Dividend yield					0	%					0	%					—

The assumptions used in the Black-Scholes option pricing model were determined as follows:

Fair Value of Common Stock. Prior to our IPO in January 2015, our board of directors considered numerous objective and subjective factors to determine the fair value of our common stock at each grant date. These factors included, but were not limited to, (i) contemporaneous valuations of common stock performed by unrelated third-party specialists; (ii) the prices for our redeemable convertible preferred stock sold to outside investors; (iii) the rights, preferences and privileges of our redeemable convertible preferred stock relative to our common stock; (iv) the lack of marketability of our common stock; (v) developments in the business; and (vi) the likelihood of achieving a liquidity event, such as an IPO or a merger or acquisition of Box, given prevailing market conditions.

Subsequent to the completion of our IPO, we use the market closing price for our Class A common stock as reported on the New York Stock Exchange.

Expected Term. The expected term represents the period that our share-based awards are expected to be outstanding. The expected term assumptions were determined based on the vesting terms, exercise terms and contractual lives of the options and ESPP purchase rights.

Expected Volatility. Since we do not have sufficient trading history of our common stock, the expected volatility was derived from the historical stock volatilities of several unrelated public companies within the same industry that we consider to be comparable to our business over a period equivalent to the expected term of the stock option grants and ESPP purchase rights.

Risk-free Interest Rate. The risk-free rate that we use is based on U.S. Treasury zero-coupon issues with remaining terms similar to the expected term on the options.

Dividend Yield. We have never declared or paid any cash dividends and do not plan to pay cash dividends in the foreseeable future, and, therefore, use an expected dividend yield of zero.