We may offer from time to time
common stock, preferred stock, debt securities, warrants, purchase contracts or units. We may offer and sell these securities to or through one or more underwriters, dealers and agents, or directly to purchasers, on a continuous or delayed basis. In
addition, certain selling securityholders to be identified in supplements to this prospectus may offer and sell these securities from time to time. Specific amounts and terms of these securities will be provided in supplements to this prospectus.
You should read this prospectus and any supplement carefully before you invest.
Investing in these
securities involves certain risks. See Risk Factors beginning on page 3 before you make your investment decision.
Neither the Securities and
Exchange Commission nor any state securities commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
The date of this prospectus is November 7, 2017