periods ended December 31, 2021. The decreases were primarily related to the smaller intangible asset base due to the impairments of certain intangible assets during the fiscal 2022 year.
Unrealized gain or loss from derivative warrant liabilities
The fair value of derivative warrant liabilities was calculated using either the Black-Scholes option model or the Monte Carlo simulation model and are revalued at each reporting period. In the three and six months ended December 31, 2022, we recognized unrealized gain of $1.4 million and $3.6 million, respectively, from the fair value adjustments.
Other (expense), net
In the three and six months ended December 31, 2022, other expense, net, increased by $1.0 million and $2.0 million, compared to the same periods ended December 31, 2021. The increases were primarily due to licensing agreements and an increase in the interest rate on our debt including amortization of our fixed term payment arrangements.
Liquidity and Capital Resources
Sources of Liquidity
We have obligations related to our loan agreements, contingent consideration related to our acquisitions, milestone payments for licensed products and manufacturing purchase commitments.
We finance our operations through a combination of sales of our common stock and warrants, borrowings under our line of credit facility and cash generated from operations.
Shelf Registrations
On September 28, 2021, we filed a shelf registration statement on Form S-3, which was declared effective by the SEC on October 7, 2021. This shelf registration statement covered the offering, issuance and sale by the Company of up to an aggregate of $100.0 million of its common stock, preferred stock, debt securities, warrants, rights and units (the “2021 Shelf”). As of December 31, 2022, approximately $82.4 million remains available under the 2021 Shelf.
On June 8, 2020, we filed a shelf registration statement on Form S-3, which was declared effective by the SEC on June 17, 2020. This shelf registration statement covered the offering, issuance and sale by the Company of up to an aggregate of $100.0 million of its common stock, preferred stock, debt securities, warrants, rights and units (the “2020 Shelf”). As of December 31, 2022, approximately $42.0 million remains available under the 2020 Shelf.
On June 4, 2021, we entered into a sales agreement with a sales agent, to provide for the offering, issuance and sale by us of up to $30.0 million of our common stock from time to time in “at-the-market” offerings under the 2020 Shelf (the “ATM Sales Agreement”). During the six months ended December 31, 2022, we issued 312,308 shares of common stock under the ATM Sales Agreement, with total net proceeds of approximately $1.5 million. As of December 31, 2022, we had approximately $3.3 million of capacity under the ATM Sales Agreement due to baby self-limitations. As our market capitalization increases, these limitations will be adjusted and we will be able to issue additional ATM sales.
Underwriting Agreements
On August 11, 2022, we closed on an underwritten public offering (“August 2022 Offering”), of (i) 1,075,290 shares of our common stock and, in lieu of common stock to certain investors, pre-funded warrants (“Pre-Funded Warrants”) to purchase 87,500 shares of our common stock, and (ii) accompanying warrants (the “Common Warrants”) to purchase 1,162,790 shares of our common stock. We received gross proceeds of $10.0 million and net proceeds of approximately $9.1 million, after deducting underwriting discounts and commissions and estimated offering expenses.