negative covenants, such as limitations on indebtedness, liens, mergers, asset transfers, certain investing activities and other matters customarily restricted in such agreements. Most of these restrictions are subject to certain minimum thresholds and exceptions. The Highbridge Loan Agreement also contains customary events of default, after which the First Lien Notes may be due and payable immediately, including, without limitation, payment defaults, material inaccuracy of representations and warranties, covenant defaults, material adverse changes, bankruptcy and insolvency proceedings, cross-defaults to certain other agreements, judgments against us, and change of control, termination of any guaranty, governmental approvals, and lien priority.
Upon the closing of the 2024 Notes, we intend to prepay the First Lien Notes in full in the amount of approximately $17.6 million, which includes the discounted prepayment premium.
Exchange Agreement with Highbridge
On April 21, 2020 we entered into a Note Purchase and Exchange Agreement, or the Exchange Agreement, which we subsequently amended on August 9, 2020, with certain funds managed by Highbridge providing for the exchange of $24.0 million aggregate principal amount of our outstanding senior convertible notes due January 15, 2025, or the 2025 Notes, for (i) $15.7 million aggregate principal amount of newly issued Second Lien Secured Notes, or the Second Lien Notes, and, together with the First Lien Notes, the Senior Notes, (ii) 11,026,086 shares of our common stock, (iii) warrants to purchase up to 4,500,000 shares of our common stock at an exercise price of $0.66 per share, and (iv) $0.3 million in accrued and unpaid interest on the 2025 Notes being exchanged. The Exchange closed on April 24, 2020. The warrants may be exercised in cash or on a cashless basis at any time through the three year anniversary of the issuance date.
The Second Lien Notes are secured, senior obligations, junior only to the First Lien Notes. The Second Lien Notes bear interest in cash at the annual rate of 7.5% or, at our election, payment in kind at an annual rate of 8.25%, payable monthly in arrears. The Second Lien Notes mature on August 9, 2023 unless earlier repurchased, redeemed or converted in accordance with their terms. The obligations under the Second Lien Notes are secured by substantially all of our assets.
We have the right to prepay the Second Lien Notes at any time, subject to a prepayment premium, which in certain circumstances we may elect to pay in our common stock, equal to the aggregate amount of interest payments through maturity. However, if the date of payment in cash of such prepayment premium is on or before August 22, 2020, the prepayment premium will be reduced by 25%.
As amended by the Amendment, effective as of the Closing Date, the holders of the Second Lien Notes will have the right to convert the aggregate principal of the Second Lien Notes (together with any applicable prepayment premium) to common stock at a price per share equal to 90% of the greater of (i) the daily volume weighted average of the price per share of the common stock, on the conversion date, or if the conversion date is not a trading date, the trading day immediately prior to the conversion date and (ii) $0.33 per share. This conversion option has a daily limit of $1,000,000 in aggregate converted principal (inclusive of principal amount of First Lien Notes that are voluntarily converted). During the quarter ended June 30, 2020, Highbridge elected to convert a total of $6.0 million of outstanding principal on the Second Lien Notes for issuance of 13,366,339 shares of common stock, which included prepayment premiums and were based off of our election of PIK interest. As of August 8. 2020, approximately $9.9 million principal amount of Second Lien Notes remained outstanding.
Subject to certain conditions, if we retain or reinvest proceeds of an asset sale pursuant to the asset sale prepayment provisions in the Exchange Agreement, the Second Lien Notes Holders shall be entitled to convert additional Second Lien Notes and the Lenders shall be entitled to convert First Lien Notes in aggregate combined principal amount equal to 45% of such net proceeds retained or reinvested (together with any applicable prepayment premium).
The Exchange Agreement contains customary terms and covenants, including without limitation: financial covenants, such as maintaining a minimum cash balance; and negative covenants, such as limitations on indebtedness, liens, mergers, asset transfers, certain investing activities and other matters customarily restricted in such agreements.