During fiscal 2019 and 2018, the Company issued 250,000 and 110,083 shares of common stock for the conversion of approximately 250,000 and 110,083 shares of Series B Convertible Preferred Stock, respectively (See Note 10).

Restricted Common Stock

The Company granted 400,000 and 1,100,000 restricted shares of common stock in fiscal 2019 and 2018, respectively. In fiscal 2018, the Company granted 600,000 and 500,000 restricted shares of common stock to its Chairman and Chief Executive Officer and President, respectively. The restricted shares are to be earned over a three-year period and cliff vest at the end of the third year from the date of grant. Stock-based compensation expense attributable to restricted stock was $0.8 million and $0.3 million in fiscal 2019 and fiscal 2018, respectively. As of September 30, 2019, there was approximately $1.6 million of unrecognized compensation expense related to restricted stock outstanding. Mr. Bajalia’s 500,000 shares of restricted common stock were fully vested on November 23, 2019 upon his passing.

A summary of restricted stock activity is presented as follows:

Warrants

No warrants were granted or exercised during fiscal 2019.

A summary of warrant activity is presented as follows: 

Stock Options

As of September 30, 2019, there were stock options outstanding under the Company’s, Second Amended and Restated 1997 Stock Option Plan and the Company’s Amended and Restated 2013 Incentive Stock Plan. Both plans were approved by the shareholders. The plans granted specified numbers of options to non-employee directors, and they authorized the Compensation Committee of the Board of Directors to grant either incentive or non-statutory stock options to employees. Vesting periods are established by the Compensation Committee at the time of grant. All stock options outstanding as of September 30, 2019 and September 30, 2018 were non-statutory stock options, had exercise prices equal to the market price on the date of grant, and had expiration dates ten years from the date of grant.

Stock-based compensation expense attributable to stock options and warrants was $1.4 million in fiscal 2019 and fiscal 2018, respectively. As of September 30, 2019, there was approximately $1.5 million of unrecognized compensation expense related to unvested stock options outstanding, and the weighted average vesting period for those options was 3.97 years.

A summary of stock option activity is as follows:

The fair value of stock options granted was made using the Black-Scholes option pricing model and the following assumptions: