Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity

Stockholders' Equity
6 Months Ended
Jun. 30, 2018
Equity [Abstract]  
Stockholders' Equity
Stockholders’ Equity
Shelf Registration and Public Offering
On May 21, 2018, we filed a shelf registration statement on Form S-3 (File No. 333-225074) with the Securities and Exchange Commission (the “SEC”), which became effective upon filing. The shelf registration allows us to sell, from time to time, an unspecified number of shares of common stock; shares of preferred stock; debt securities; warrants to purchase shares of common stock, preferred stock, or other securities; purchase contracts; and units representing two or more of the foregoing securities.
On May 29, 2018, we consummated an underwritten public offering of 8.05 million shares of our common stock, which included 1.05 million shares sold pursuant to the underwriters’ full exercise of their option to purchase additional shares. The offering was priced at $57.00 per share for total gross proceeds of $458.9 million. The aggregate net proceeds to us were $441.8 million, after deducting underwriting discounts and offering expenses in the aggregate amount of $17.1 million.
Increase in Authorized Shares
On June 5, 2018, our stockholders approved an amendment to the Company’s Certificate of Incorporation to increase the authorized number of shares of our Common Stock from 125,000,000 to 250,000,000 shares. Our board of directors had previously approved the amendment in 2018.
Stock Repurchase Program
In May 2014, our board of directors approved a share repurchase program authorizing the repurchase of up to $50.0 million of our outstanding common stock for a period of up to one year after the approval date. Shares repurchased under the plan are retired. Our board of directors approved a one year extension of this program in 2015, 2016 and 2017. This program expired in May 2018.
There was no repurchase activity during the three and six months ended June 30, 2018 and 2017.