Commencing with options granted in September 2015, options granted to existing employees have the same terms as the Market Return Options, and options granted to new employees consist ofone-third Time-Based Options andtwo-thirds Market Return Options.
In 2015 and 2016, options were granted to employees following the net exercise of the options they received in 2007 in exchange for options that had previously been granted in DJO’s predecessor company (Rollover Options), which were scheduled to expire in 2015 and 2016, respectively. These new options were fully vested on the date of grant and have a term of ten years (Vested Options).
Except for options granted to the Chairman of the Board and two other board members as described below, options are typically granted annually to members of our Board of Directors who are not affiliates of Blackstone (referred to as Director Service Options). The Director Service Options vest in increments of 33 1/3% per year on each of the first through third anniversary dates of the grant date, contingent upon the optionee’s continued service as a director. The options granted to the Chairman of the Board and the two other board members vest as follows:one-third of the stock option grant vests in increments of 33 1/3% per year on each of the first through third anniversary dates from the grant date contingent upon the optionee’s continued service as a director; and, as amended in July 2015,two-thirds of the stock option grant will vest in the same manner as the Market Return Options.
Stock-Based Compensation
During the year ended December 31, 2017, the compensation committee granted 1,475,000 options to employees, of which 1,047,501 were Market Return Options and 427,499 were Time-Based Options. Additionally, the compensation committee granted 13,800 Director Service Options to members of the Board of Directors. The weighted average grant date fair value of the Time-Based Options and Director Service Options granted during the year ended December 31, 2017 was $6.30 and $6.60, respectively.
During the year ended December 31, 2016, the compensation committee granted 2,015,318 options to employees, of which 1,356,164 were Market Return Options, 484,336 were Time-Based Options and 174,818 were Vested Options. Additionally, the compensation committee granted 18,800 Director Service Options to members of the Board of Directors and 10,000 Market Return Options tonon-employees. The weighted average grant date fair values of the Time-Based Options, Vested Options and Director Service Options granted during the year ended December 31, 2016 were $6.12, $5.98 and $5.25, respectively. In addition, during the year ended December 31, 2016, we granted 121,507 restricted stock units (RSUs) to Michael C. Eklund, our new chief financial officer and chief operating officer. The RSUs vest over four years, with 25% vesting on October 3, 2017 and an additional 25% vesting on each October 3 thereafter, contingent upon his continued employment with the Company on each vesting date. The grant date fair value of the RSUs was $16.46.
During the year ended December 31, 2015, the compensation committee granted 1,343,621 options to employees, of which 1,065,002 were Performance Options, 257,498 were Time-Based Options and 21,121 were Vested Options. The weighted average grant date fair values of the Time-Based Options, Vested Options and Director Service Options granted during the year ended December 31, 2015 were $6.09, $5.27 and $6.92, respectively.
The fair value of each option award is estimated on the date of grant, or modification, using the Black-Scholes option pricing model for service based awards, and a binomial model for market based awards. In estimating fair value for options issued under the 2007 Plan, expected volatility was based on historical volatility of comparable publicly-traded companies. As our historical share option exercise experience does not provide a reasonable basis upon which to estimate the expected term, we used the simplified method. Expected life is calculated in two tranches based on the employment level defined as executive or employee. The risk-free rate used in calculating fair value of stock options for periods within the expected term of the option is based on the U.S. Treasury yield bond curve in effect on the date of grant.
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