15. Stockholders’ Equity

Stock-based Compensation

The following table summarizes the stock-based compensation expense from stock option, employee stock purchase programs and restricted Common Stock awards and warrants for the three and six months ended June 30, 2019 and 2018:

 

For the three months ended June 30, 2019 and 2018, approximately $0.8 million and $0.8 million, respectively, of stock-based compensation expense was included in research and development expenses in connection with equity grants made to employees and consultants and approximately $2.6 million and $2.4 million, respectively, was included in general and administrative expenses in connection with grants made to employees, members of the board of directors and consultants.

For the six months ended June 30, 2019 and 2018, approximately $1.4 million and $3.1 million, respectively, of stock-based compensation expense was included in research and development expenses in connection with equity grants made to employees and consultants and approximately $5.3 million and $4.8 million, respectively, was included in general and administrative expenses in connection with grants made to employees, members of the board of directors and consultants.

Stock Options

The following table summarizes Fortress stock option activities excluding activity related to Fortress partner companies:

 

As of June 30, 2019, Fortress had no unrecognized stock-based compensation expense related to options.

Restricted Stock and Restricted Stock Units

The following table summarizes Fortress restricted stock awards and restricted stock units activities, excluding activities related to Fortress Companies:

 

As of June 30, 2019, the Company had unrecognized stock-based compensation expense related to restricted stock and restricted stock unit awards of approximately $13.6 million and $2.1 million, respectively, which is expected to be recognized over the remaining weighted-average vesting period of 5.2 years and 2.2 years, respectively.

Warrants

The following table summarizes Fortress warrant activities, excluding activities related to Fortress Companies:

 

Employee Stock Purchase Plan

Eligible employees can purchase the Company’s Common Stock at the end of a predetermined offering period at 85% of the lower of the fair market value at the beginning or end of the offering period. The ESPP is compensatory and results in stock-based compensation expense.

As of June 30, 2019, 410,728 shares have been purchased and 589,272 shares are available for future sale under the Company’s ESPP. Share-based compensation expense recorded was approximately $19,000 and $43,000, respectively for the three months ended June 30, 2019 and 2018, and was approximately $39,000 and $81,000, respectively, for the six months ended June 30, 2019 and 2018.

Capital Raises

At-the-Market Offering

Pursuant to the terms of the Company’s Amended and Restated At Market Issuance Sales Agreement, or Sales Agreement, with B. Riley FBR, Inc. (“B. Riley,” f/k/a MLV & Co. LLC, and FBR Capital Markets & Co.) (the “ATM”), for the three and six month periods ended June 30, 2019, the Company issued approximately  4.5 million and 7.4 million shares of common stock at an average price of $1.72 and $1.88 per share for gross proceeds of $7.7 million and $14.0 million, respectively. In connection with these sales, the Company paid aggregate fees of approximately $0.3 million. The Sales Agreement terminates on August 17, 2019.

These shares were sold pursuant to the current shelf registration statement on Form S‑3; approximately $6.8 million of the shelf remains available for sale at June 30, 2019.

2019 At-the-Market Offering

On June 28, 2019, the Company entered into an At Market Issuance Sales Agreement (“2019 ATM”), with Cantor Fitzgerald & Co., Oppenheimer & Co., Inc., H.C. Wainwright & Co. Inc., Jones Trading Institutional Services LLC and B. Riley FBR, Inc., (each an "Agent" and collectively, the "Agents"). Also June 28, 2019, the Company filed the Second Amendment to Registration Statement No. 333-226089 on Form S-3 (the “Registration Statement”) which, upon effectiveness, will permit the Company to issue and sell shares of its common stock having an aggregate offering price of up to $50.0 million from time to time through the Agents under the 2019 ATM. Under the 2019 ATM, the Company pays the Agents a commission rate of up to 3.0% of the gross proceeds from the sale of any shares of common stock.

The 2019 ATM terminates on the earlier of three years from the date of effectiveness of the Form S-3 or the sale of all shares of common stock registered on the Registration Statement. The Company was notified by the SEC that the S-3 was declared effective on July 23, 2019.

Checkpoint Therapeutics, Inc.

Checkpoint At-the-Market Offering

In November 2017, Checkpoint filed a shelf registration statement on Form S‑3 (the "Checkpoint S‑3"), which was declared effective in December 2017. Under the Checkpoint S‑3, Checkpoint may sell up to a total of $100 million of its securities. In connection with the Checkpoint S‑3, Checkpoint entered into an At-the-Market Issuance Sales Agreement (the "Checkpoint ATM") with Cantor Fitzgerald & Co., Ladenburg Thalmann & Co. Inc. and H.C. Wainwright & Co., LLC (each an "Agent" and collectively, the "Agents"), relating to the sale of shares of common stock. Under the Checkpoint ATM, Checkpoint pays the Agents a commission rate of up to 3.0% of the gross proceeds from the sale of any shares of common stock.

During the three and six months ended June 30, 2019, Checkpoint sold a total of 997,957 and 1,088,226 of its common stock, respectively, under the Checkpoint ATM for aggregate total gross proceeds of approximately $4.1 million and $4.5 million at an average selling price of $4.12 per share. Pursuant to the Founders Agreement, Checkpoint issued 24,941 and 27,195 shares of common stock to Fortress during the three and six months ended June 30, 2019, respectively, for the ATM offering noted above. No sales were made during the three and six months ended June 30, 2018 under the Checkpoint ATM.

In July 2019, Checkpoint was added to the Russell 2000® Index.

Approximately $61.5 million of the shelf remains available for sale under the Checkpoint S‑3, following the offerings noted above. Checkpoint may offer the securities under the Checkpoint S‑3 from time to time in response to market conditions or other circumstances if it believes such a plan of financing is in the best interests of its stockholders.

Mustang Bio, Inc.

Mustang At-the-Market Offering

On July 13, 2018, Mustang filed a shelf registration statement No. 333-226175 on Form S-3, as amended on July 20, 2018 (the "Mustang S-3"), which was declared effective in August 2018. Under the Mustang S-3, Mustang may sell up to a total of $75.0 million of its securities. In connection with the Mustang S-3, Mustang entered into an At-the-Market Issuance Sales Agreement (the "Mustang ATM") with B. Riley FBR, Inc., Cantor Fitzgerald & Co., National Securities Corporation, and Oppenheimer & Co. Inc. (each an "Agent" and collectively, the "Agents"), relating to the sale of shares of common stock. Under the Mustang ATM, Mustang pays the Agents a commission rate of up to 3.0% of the gross proceeds from the sale of any shares of common stock.

During the three months and six months ended June 30, 2019, Mustang issued approximately 3.5 million shares of common stock at an average price of $6.42 per share for gross proceeds of $22.5 million. In connection with these sales, Mustang paid aggregate fees of approximately $0.5 million, for net proceeds of approximately $22.0 million. No sales where made under the Mustang ATM in 2018.

Mustang Public Offering of Common Stock

In  May 2019, Mustang announced the pricing of an underwritten public offering, whereby it sold 6,875,000 shares of its common stock, (plus a 30-day option to purchase up to an additional 1,031,250 shares of common stock, which was exercised in May 2019) at a price of $4.00 per share for gross proceeds of approximately $31.6 million, before deducting underwriting discounts and commissions and offering expenses. The shares were sold under the Mustang S-3. Mustang paid aggregate fees of approximately $2.1 million and received approximately $29.5 million of net proceeds.

As of June 30, 2019, approximately $20.9 million of the Mustang S-3 remains available for sales of securities.