7. Debt

L2 Capital Debt

On January 31, 2018, the Company signed a promissory note in the aggregate principal amount of up to $0.84 million (the “L2 Note”) for an aggregate purchase price of up to $0.75 million and warrants to purchase up to an aggregate of 68,257 shares of common stock (the “Warrants”) at an exercise price of $3.31 per share. The maturity date was six months from date of funding. The L2 Note’s interest rate was 8% per year and a default interest rate of 18% per year.

On May 14, 2018, the Company closed on an underwritten public offering of units, consisting of convertible preferred stock and warrants, for gross proceeds of $15.0 million. Part of the proceeds from this offering were used to pay off the outstanding debt with L2 Capital. The total payoff was $1.1 million, with $0.7 million in principal and $0.4 million in interest.

Hercules and MEF I, LP/Anson Investments Debt Exchange

On January 3, 2018, the Company entered into an Assignment Agreement (the “Assignment Agreement”) with MEF I, LP and Anson Investments Master Fund (collectively the “Assignees” and each an “Assignee”), Hercules Technology III, L.P. (“HT III”) and Hercules Capital, Inc. (“HC” and, together with HT III, “Hercules”), pursuant to which Hercules assigned to the Assignees all amounts remaining due under the Loan and Security Agreement, dated June 30, 2014, as amended, between the Company and Hercules (the “Loan and Security Agreement”) and (2) the note (the “Hercules Note”) between the Company and Hercules evidencing the amounts due under the Loan and Security Agreement. The total amount assigned by Hercules to the Assignees in the aggregate was $2.3 million and was secured by the same collateral underlying the Loan and Security Agreement. Subsequently, the Company entered into an exchange agreement pursuant to which the Assignees agreed to exchange the Hercules Term Loan obligation acquired by them for two senior secured convertible promissory notes issued by the Company, each in the principal amount of $1.1 million for an aggregate principal amount of $2.2 million, (the “Exchange Notes”). The Exchange Notes were scheduled to mature on February 3, 2019 (the “Maturity Date”). The Exchange Notes had interest at a rate of 15% per annum. The Exchange Notes were secured by a first priority security interest in substantially all of the Company assets, including intellectual property, and contains covenants restricting payments to certain of our affiliates.

On May 14, 2018, the Company closed on an underwritten public offering of units, consisting of convertible preferred stock and warrants, for gross proceeds of $15.0 million. Part of the proceeds from this offering were used to pay off the outstanding debt with MEF I, L.P and Anson Investments. The total payoff was $1.6 million, with $1.4 million in principal and $0.2 million in interest.

North Stadium Term Loan – Related Party

On July 28, 2017, the Company entered into a $2.5 million term loan (the “North Stadium Loan”) with North Stadium Investments, LLC (“North Stadium”), a company owned and controlled by the Company’s Chief Executive Officer and Chairman of the Board. The North Stadium Loan bore interest at 10% per annum and required the Company to make monthly interest only payments from September 5, 2017 through July 5, 2018. All principal and unpaid interest (if any) under the North Stadium Loan was due and payable on July 28, 2018. The North Stadium Loan was secured by substantially all of the Company’s assets but was junior to security interest in assets encumbered by the Hercules Term Loan (see below). In connection with the North Stadium Loan the Company also issued North Stadium a warrant to purchase up to 1,834 shares of the Company’s common stock at a purchase price of $151.20 per share, subject to a 5-year term. The relative estimated value of the warrants on the date of grant approximated $0.2 million, which was being amortized as interest expense over the life of the term loan.

On October 1, 2018, CTL Medical assumed the North Stadium Term Loan debt as part of the sale of the retail spine business. As of December 31, 2018, the Company has been released by North Stadium from any and all obligations related to this debt.

Hercules Term Loan

On June 30, 2014, the Company entered into a Loan and Security Agreement with Hercules which provided the Company with a $20.0 million term loan. The Hercules Term Loan matured on January 1, 2018. The Hercules Term Loan included a $0.2 million closing fee, which was paid to Hercules on the closing date of the loan. The closing fee was recorded as a debt discount and was being amortized to interest expense over the life of the loan. The Hercules Term Loan also included a non-refundable final payment fee of $1.7 million. The final payment fee was being accrued and recorded to interest expense over the life of the loan.

On January 3, 2018, the Hercules Term Loan and all amounts owing thereunder was assigned to MEF I and Anson Investments. See discussion above under “Hercules and MEF I, LP/Anson Investments Debt Exchange” for a more detailed description of that transaction.