NOTE 7 — SHARE-BASED COMPENSATION AND WARRANTS

Stock Option Plans

Presented below is a summary of the number of shares authorized, outstanding, and available for future grants under each of the Company’s stock option plans as of December 31, 2021 (in thousands):

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Stock Options Outstanding

The following table sets forth a summary of the stock option activity under all of the Company’s stock option plans for the six months ended December 31, 2021 (shares in thousands):

For the six months ended December 31, 2021, the aggregate fair value of stock options granted for approximately 0.1 million shares of common stock that provide solely for time-based vesting, amounted to $0.6 million or approximately $5.72 per share as of the grant dates. Fair value was computed using the BSM option-pricing model and will result in the recognition of compensation cost ratably over the expected vesting period of the stock options. For the six months ended December 31, 2021, the fair value of stock options was estimated on the date of grant, with the following weighted-average assumptions:

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Share-based compensation expense for the three and six months ended December 31, 2021 and 2020 is included under the following captions in the unaudited condensed consolidated statements of operations (in thousands):

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Unrecognized share-based compensation expense is approximately $6.9 million as of December 31, 2021. This amount is expected to be recognized over a weighted average period of 2.4 years.

Warrants

In connection with the Underwritten Offering discussed in Note 6, the Company issued 1,661,461 Pre-Funded Warrants to purchase 1,661,461 shares of common stock at an issuance price of $6.49 per warrant for gross proceeds of $10.8 million. The Pre-Funded Warrants may be exercised at any time by paying the exercise price of $0.01 per share, subject to the terms discussed in Note 6.

In addition, the Company has issued warrants in conjunction with various debt and equity financings and for services. The following table sets forth a summary of the warrant activity (excluding the Pre-Funded Warrants) for the six months ended December 31, 2021 (shares in thousands):

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