XML 41 R31.htm IDEA: XBRL DOCUMENT v3.21.1
Stock Incentive Plans (Tables)
 3 Months Ended
Mar. 31, 2021
Share-based Payment Arrangement [Abstract]  
Summary of Option, Unvested RSU Activity under 2014 Equity Incentive Plan and 2016 Inducement Equity Incentive Plan and Related Information
The following table summarizes option and RSU activity under the Company’s 2014 Equity Incentive Plan, 2016 Inducement Equity Incentive Plan, and 2019 Inducement Equity Incentive Plan, and related information:
Shares
Available
for Grant		Stock
Options
Outstanding		Weighted-
Average
Exercise
Price		Number of
RSU Shares		Weighted-
Average
Grant Date
Fair Value
Balance—December 31, 2020672,968 2,670,398 $21.92 1,884,866 $28.42 
Additional shares authorized1,977,647 — — — — 
Common stock awards for services(1,339)— — — — 
RSUs granted(246,379)— — 246,379 82.62 
RSUs vested— — — (207,881)24.06 
Options granted(127,925)127,925 81.06 — — 
Options exercised— (139,579)13.99 — — 
Repurchase of common stock under employee incentive plans74,434 — — — — 
RSUs forfeited69,945 — — (69,945)29.32 
Options forfeited66,213 (66,213)25.70 — — 
Options expired250 (250)22.59 — — 
Balance—March 31, 20212,485,814 2,592,281 $25.17 1,853,419 $36.14 
Summary of Options Outstanding and Exercisable Vested or Expected to Vest
Options outstanding that have vested and are expected to vest at March 31, 2021 are as follows:
Number of Shares Issued
(In thousands)		Weighted-Average
Exercise Price		Weighted-Average Remaining Contractual Life (Years)Aggregate Intrinsic Value
(In thousands)
Vested1,045 $16.09 6.54$54,318 
Expected to vest1,398 31.91 8.6852,508 
Total2,443 $106,826 
Weighted-Average Assumptions Used to Estimate Fair Values of Share-Based Awards
The estimated fair values of employee stock options and ESPP shares were estimated using the Black-Scholes option pricing model based on the following weighted average assumptions:
Three Months Ended March 31,
20212020
Employee stock options
Expected term (in years)6.06.0
Expected volatility77.69%74.00%
Risk-free interest rate0.68%1.35%
Expected dividend yield—%—%
Employee stock purchase plan
Expected term (in years)0.50.5
Expected volatility53.10%62.56%
Risk-free interest rate0.09%1.57%
Expected dividend yield—%—%
Summary of Expense Relating to Employee and Nonemployee Stock-Based Payment Awards from Stock Options and RSUs
The following table summarizes stock-based compensation expense relating to employee and non-employee stock-based awards for the three months ended March 31, 2021 and 2020, included in the condensed consolidated statements of operations as follows (in thousands):
Three Months Ended March 31,
20212020
Cost of testing services$395 $247 
Cost of product76 59 
Cost of digital and other108 59 
Research and development1,358 810 
Sales and marketing1,659 971 
General and administrative2,951 2,113 
Total$6,547 $4,259