Stockholders' equity | Stockholders’ equity The Company is presently authorized to issue up to 240 million shares of stock, of which 40 million are authorized as preferred stock and 200 million as common stock. Common stock The holders of the common stock are entitled to one vote for each share held at all meetings of stockholders. Dividends and distribution of assets of the Company in the event of liquidation are subject to the preferential rights of any outstanding preferred shares. At June 30, 2017 , the Company had reserved 227,203 shares of common stock for the exercise of options. Restricted stock The Company grants restricted common stock to the Chairman of the Board of Directors as part of his compensation package. Generally, the shares are fully vested upon the third anniversary of the grant date. Unvested shares can be canceled upon termination of the Chairman’s services. A summary of the Company’s unvested shares of restricted stock as of June 30, 2017 , is as follows: Shares Weighted average grant date fair value Unvested at December 31, 2016 4,169 $ 7.72 Granted 1,751 14.20 Vested (1,532 ) 7.88 Unvested at June 30, 2017 4,388 $ 10.25 During the six months ended June 30, 2017 and 2016 , the Company expensed $12,070 and $8,260 , respectively, related to the Chairman’s restricted stock awards. At June 30, 2017 , the balance of unearned share-based compensation to be expensed in future periods related to the restricted stock awards is $44,982 . The period over which the unearned share-based compensation is expected to be earned is approximately three years. Stock options In 2006, the Company established its 2006 Equity Incentive Plan (the “2006 Plan”). The 2006 Plan provided for the issuance of incentive stock options to employees of the Company and non‑qualified stock options and awards of restricted and direct stock purchases to directors, officers, employees, and consultants of the Company. In accordance with its original terms, no further shares may be granted under the 2006 Plan subsequent to March 18, 2016. All outstanding awards under the 2006 Plan will continue until their individual termination dates. In March 2016, the Company’s Board of Directors adopted the AquaBounty Technologies, Inc. 2016 Equity Incentive Plan (the “2016 Plan”) to replace the 2006 Plan. The 2016 Plan provides for the issuance of incentive stock options, non‑qualified stock options, and awards of restricted and direct stock purchases to directors, officers, employees, and consultants of the Company. The aggregate number of shares of common stock that may be issued pursuant to awards granted under the 2016 Plan cannot exceed 450,000 . The 2016 Plan was approved by the Company’s shareholders at its Annual Meeting on April 26, 2016. The Company’s option activity under the 2006 Plan and the 2016 Plan is summarized as follows: Number of Weighted Outstanding at December 31, 2016 185,591 $ 7.89 Issued 52,500 14.20 Exercised (8,334 ) 3.30 Expired (2,554 ) 19.50 Outstanding at June 30, 2017 227,203 $ 9.39 Exercisable at June 30, 2017 179,500 $ 8.17 Unless otherwise indicated, options issued to employees, members of the Board of Directors, and non-employees are vested over one to three years and are exercisable for a term of ten years from the date of issuance. The weighted average fair value of stock options granted during the six months ended June 30, 2017, was $4.55 . The intrinsic value of options exercised during the six months ended June 30, 2017, was $43,420 . The total intrinsic value of all options outstanding was $441,390 and $602,773 at June 30, 2017 , and December 31, 2016 , respectively. The total intrinsic value of exercisable options was $439,494 and $597,872 at June 30, 2017 , and December 31, 2016 , respectively. The following table summarizes information about options outstanding and exercisable at June 30, 2017 : Weighted average exercise price of outstanding options Number of options outstanding Weighted average remaining estimated life (in years) Number of options exercisable Weighted average exercise price of outstanding and exercisable options $3.30 79,337 2.0 79,337 $3.60 800 5.0 800 $5.70 10,336 7.7 10,006 $6.90 29,038 3.9 28,016 $7.50 15,837 5.8 15,837 $9.60 8,300 8.2 8,300 $9.90 800 1.0 800 $10.50 1,600 6.0 1,600 $10.80 2,400 7.0 2,400 $14.20 52,500 9.8 6,149 $23.40 26,255 6.6 26,255 227,203 179,500 $8.17 Total share-based compensation on stock-option grants amounted to $36,682 and $106,402 for the six months ended June 30, 2017 and 2016 , respectively. At June 30, 2017 , the balance of unearned share-based compensation to be expensed in future periods related to unvested share-based awards was $216,447 . The period over which the unearned share-based compensation is expected to be earned is approximately three years. |