Net Income Per Share

6 Months Ended

Jun. 30, 2016

5. NET INCOME PER SHARE

On May 1, 2013, pursuant to the Second Modified Fifth Amended Plan of Reorganization of Ambac (the "Reorganization Plan"), 45,000,000 shares of new common stock at par value of $0.01 per share and 5,047,138 of warrants were issued. Warrants entitled such holders to acquire up to 5,047,138 shares of new common stock at an exercise price of $16.67 per share at any time on or prior to April 30, 2023. For the six months ended June 30, 2016 and 2015, 136 and 398 warrants were exercised, respectively, resulting in an issuance of 136 and 207 shares of common stock, respectively.

On June 30, 2015, the Board of Directors of Ambac authorized the establishment of a warrant repurchase program that permits the repurchase of up to $10,000 of warrants. For the six months ended June 30, 2016, Ambac repurchased 228,500 warrants at a cost of $1,610. As of June 30, 2016, Ambac has repurchased 860,100 warrants totaling $6,983, (average cost of $8.12 per warrant) leaving 4,178,901 warrants outstanding.

Basic net income per share is computed by dividing net income attributable to common stockholders by the weighted-average number of common shares outstanding and vested restricted stock units. Diluted net income per share is computed by dividing net income attributable to common stockholders by the weighted-average number of common shares used for basic earnings per share plus all potential dilutive common shares outstanding during the period. All potential dilutive common shares outstanding consider common stock deliverable pursuant to warrants issued under the Reorganization Plan and vested and unvested options, unvested restricted stock and performance stock units granted under employee and director compensation plans.

The following table provides a reconciliation of the common shares used for basic net income per share to the diluted shares used for diluted net income per share:



	Three Months Ended June 30,		Six Months Ended June 30,
	2016	2015	2016	2015
Basic weighted average shares outstanding	45,212,484	45,190,089	45,194,731	45,173,239
Effect of potential dilutive shares:
Warrants	—	1,480,990	—	1,625,901
Stock options	—	8,409	—	10,625
Restricted stock units	104,457	18,242	80,680	21,628
Performance stock units	58,147	5,042	34,132	4,094
Diluted weighted average shares outstanding	45,375,088	46,702,772	45,309,543	46,835,487

Antidilutive securities for the three and six months ended June 30, 2016 included stock options and warrants to purchase 176,668 and 4,178,901 shares of common stock, respectively, where the exercise price was greater than the average market price and 23,334 restricted stock units. Antidilutive securities for the three and six months ended June 30, 2015 included stock options to purchase 110,000 shares of common stock where the exercise price was greater than the average market price.