Rights and Preferences
Holders of our common stock have no preemptive, conversion, subscription or other rights, and there are no redemption or sinking fund provisions applicable to our common stock. The rights, preferences and privileges of the holders of our common stock are subject to and may be adversely affected by the rights of the holders of shares of any series of our convertible preferred stock that we may designate in the future.
Preferred Stock
Our board of directors has the authority, without further action by our stockholders, to issue up to 10,000,000 shares of preferred stock in one or more series and to fix the rights, preferences, privileges and restrictions thereof. These rights, preferences and privileges could include dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences, sinking fund terms and the number of shares constituting, or the designation of, such series, any or all of which may be greater than the rights of common stock. The issuance of our preferred stock could adversely affect the voting power of holders of common stock and the likelihood that such holders will receive dividend payments and payments upon our liquidation. In addition, the issuance of preferred stock could have the effect of delaying, deferring or preventing a change in control of our company or other corporate action. As of September 30, 2021, no shares of preferred stock were outstanding.
Options
As of September 30, 2021, we had outstanding options to purchase 5,280,284 shares of our common stock, with a per share weighted-average exercise price of $9.82, under our 2015 Equity Incentive Plan, 2018 Equity Incentive Plan and our 2021 Employment Inducement Incentive Award Plan.
Warrants
In December 2020, we issued and sold, in a private placement transaction, warrants to purchase 27,480,719 shares of our common stock, with a per share weighted average exercise price of $3.34 per share of Common Stock, of which $3.33 per share was paid by each holder of such warrants at the time of purchase (such warrants, the “Pre-Funded Warrants”).
The material terms and provisions of the Pre-Funded Warrants to purchase shares of Common Stock are summarized below. This summary is subject to and qualified in its entirety by the form of pre-funded warrant, which was filed with the SEC as an exhibit to the Company’s Form 8-K on December 28, 2020.
Exercisability. The holder may exercise the Pre-Funded Warrants at any time. There is no expiration date for the Pre-Funded Warrants. Notwithstanding the foregoing, certain holders will be prohibited from exercising such warrants into shares of our common stock if, as a result of such exercise, the holder, together with its affiliates, would own more than 9.99% of the total number of shares of our common stock then issued and outstanding. The Pre-Funded Warrants are exercisable, at the option of each holder, in whole or in part, by delivering to us a duly executed exercise notice accompanied by payment in full for the number of shares of our common stock purchased upon such exercise (except in the case of a cashless exercise as discussed below).
Exercise Price. The exercise price of each Pre-Funded Warrant is $3.34 per share of Common Stock, of which $3.33 per share was paid by each purchaser of Pre-Funded Warrants at time of purchase. The exercise price of the warrants is subject to appropriate adjustment in the event of stock dividends, subdivisions, stock splits, stock combinations, reclassifications or reorganizations affecting our common stock.
Payment of Exercise Price. The warrant holders have the option to provide payment of the exercise price of the shares being acquired upon exercise of the warrants (i) by wire transfer or cashier’s check, or, in certain circumstances as described below (ii) by cashless exercise.
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