The Company has two stock-based compensation plans. The 2006 Stock Incentive Plan was adopted in 2006 (“2006 Plan”) and had options granted under it through April 12, 2016. On June 1, 2016, the shareholders ratified the IAI 2016 Stock Incentive Plan (“2016 Plan”), which had been approved by the Board of Directors on April 4, 2016.

The Company recognizes compensation costs for those shares expected to vest on a straight-line basis over the requisite service period of the awards. Generally such options vest over periods of six months to two years. The fair values of option awards granted in 2018 and 2017 were estimated using the Black-Sholes option pricing model under the following assumptions:

2016 Stock Incentive Plan

The 2016 Plan became effective June 1, 2016, and expires April 4, 2026. The 2016 Plan provided for the granting of equity awards to key employees, including officers and directors. The maximum number of shares for which equity awards may be granted under the 2016 Plan is 1,000,000. Options under the 2016 Plan expire no later than ten years from the date of grant or when employment ceases, whichever comes first, and vest over periods determined by the Board of Directors. The minimum exercise price of each option is the quoted market price of the Company’s stock on the date of grant. At December 31, 2018 and 2017, there were 373,000 and 222,000 options, respectively, issued under the 2016 Plan, of which 224,500 and 0 were exercisable, respectively.

2006 Stock Incentive Plan

The 2006 Plan became effective May 18, 2006, and expired April 12, 2016. The 2006 Plan provides for the granting of equity awards to key employees, including officers and directors. The maximum number of shares for which equity awards could be granted under the 2006 Plan was 1,950,000. Options under the 2006 Plan expire no later than ten years from the date of grant or when employment ceases, whichever comes first, and vested over periods determined by the Board of Directors. There were 1,003,500 and 1,056,000 unexpired exercisable options remaining from the 2006 Plan at December 31, 2018 and 2017, respectively.

The status of the options issued under the foregoing option plans as of December 31, 2018, and changes during the year ended December 31, 2018, was as follows:

Nonvested stock option awards as of December 31, 2018, and changes during the year ended December 31, 2018, were as follows:

As of December 31, 2018, unrecognized compensation cost associated with non-vested share-based employee and non-employee compensation totaled $7,533, which is expected to be recognized over a weighted average period of 5 months.