6. Borrowings

Borrowings consist of the following (in thousands):

	September 30, 2017			December 31, 2016
Facility Financing Obligation (2019 Notes)
Principal amount	$	60,000		$	75,000
Unamortized debt discount		(2,058	)		(3,661	)
Net carrying amount	$	57,942		$	71,339
Senior Convertible Notes (2018 notes)
Principal amount	$	27,690		$	27,690
Unamortized premium		244			426
Unaccreted debt issuance costs		(277	)		(481	)
Net carrying amount	$	27,657		$	27,635
Note payable to principal stockholder - net carrying amount	$	79,666		$	49,521

On October 23, 2017 the Company entered into an exchange agreement with the holders of the 2018 notes and a Fourth Amendment to the Facility Agreement as further discussed in Note 15- Subsequent Events. The information in this note has not been updated for these subsequent events.

Facility Financing Obligation (2019 Notes) – On April 18, 2017, the Company entered into an Exchange Agreement with Deerfield pursuant to which the Company agreed to, among other things, (i) repay $4.0 million principal amount under the Tranche B notes; (ii) exchange $1.0 million principal amount under the Tranche B notes for 869,565 shares of the Company’s common stock (the “Tranche B Exchange Shares”); and (iii) exchange $5.0 million principal amount under the 2019 notes for 4,347,826 shares of the Company’s common stock (together with the “Tranche B Exchange Shares,” the “April Exchange Shares”). The exchange price for the Exchange Shares was $1.15 per share.

The Company determined that, since the principal amount repaid and exchanged under the Tranche B notes and the principal amount exchanged under the 2019 notes represented the principal amount that would have otherwise become due and payable in May and July of 2017 under the Tranche B notes and 2019 notes, respectively, the extinguishment of the May and July 2017 payments was not considered to be a troubled debt restructuring. Accordingly, the Company accounted for the transaction by recording a loss on extinguishment of debt of $0.3 million at April 18, 2017 which was calculated as the difference between the reacquisition price and the net carrying value of the related debt. The reacquisition price was calculated using the $4.0 million cash repayment and the fair value of the April Exchange Shares on April 18, 2017. The fair value of the April Exchange Shares was determined to be $1.22 per share representing the closing trading price of the Company’s common stock on The NASDAQ Global Market on April 18, 2017.

On June 29, 2017, the Company entered into the Third Amendment with Deerfield, pursuant to which the Company agreed to, among other things, (i) exchange $5.0 million principal amount under the Company’s 2019 notes for 3,584,230 shares of the Company’s common stock (the “June Exchange Shares”) at an exchange price of $1.395 per share and (ii) amend the Facility Agreement with Deerfield, to (A) defer the payment of $10.0 million in principal amount of the 2019 notes from the original July 18, 2017 due date to August 31, 2017, which was further deferred to October 31, 2017 upon the Company’s delivery on August 31, 2017 and October 30, 2017 of a written certification to Deerfield that certain conditions had been met, including that no event of default under the Facility Agreement had occurred, Michael Castagna remains the Company’s Chief Executive Officer, the Company received the advance from The Mann Group (see Note 5 — Related-Party Arrangements), the Company had at least $10.0 million in cash and cash equivalents on hand, no material adverse effect on the Company had occurred, the engagement letter between the Company and Greenhill & Co., Inc. (“Greenhill”) remained in full force and effect and Greenhill had remained actively engaged in exploring capital structure and financial alternatives on behalf of the Company in accordance with such engagement letter (collectively, the “Extension Conditions”), and (B) amend the Company’s financial covenant under the Facility Agreement to provide that, if the Extension Conditions remain satisfied, the obligation under the Facility Agreement to maintain at least $25.0 million in cash and cash equivalents as of the end of each quarter will be reduced to $10.0 million as of August 31, 2017, September 30, 2017, October 31, 2017 and December 31, 2017.

The Company determined that since the principal amount repaid and exchanged under the 2019 notes represented the principal amount that would have otherwise become due and payable under the 2019 notes, the $5.0 million prepayment was not considered to be a troubled debt restructuring. Accordingly, the Company accounted for the transaction by recording a loss on extinguishment of debt of $0.5 million on June 29, 2017 which was calculated as the difference between the reacquisition price and the net carrying value of the related debt. The net carrying value of the related debt includes the acceleration of the debt discount and issuance costs amounting to approximately $0.3 million as a result of the transaction. The reacquisition price was calculated using the fair value of the June Exchange Shares on June 29, 2017. The fair value of the Exchange Shares was determined to be $1.45 per share representing the closing trading price of the Company’s common stock on The NASDAQ Global Market on June 29, 2017.

As of September 30, 2017, there was $45.0 million principal amount of 2019 notes and $15.0 million principal amount of Tranche B notes outstanding. The 2019 notes accrue interest at an annual rate of 9.75% and the Tranche B notes accrue interest at an annual rate of 8.75%. Interest is paid quarterly in arrears on the last day of each March, June, September and December. The Facility Financing Obligation principal repayment schedule is comprised of payments which began on July 1, 2016 and end on December 9, 2019. As of September 30, 2017, future payments for the years ending December 31, 2017, 2018, and 2019 are $10.0 million, $20.0 million and $30.0 million, respectively.

In connection with the Facility Agreement, on July 1, 2013, the Company entered into a Milestone Rights Purchase Agreement (the “Milestone Agreement”) with Deerfield and Horizon Santé FLML SÁRL (collectively, the “Milestone Purchasers”), which requires the Company to make contingent payments to the Milestone Purchasers, totaling up to $90.0 million, upon the Company achieving specified commercialization milestones (the “Milestone Rights”). As of September 30, 2017 and December 31, 2016, the remaining milestone rights liability balance was $8.9 million. The Company currently estimates that it will reach the next milestone in the third quarter of 2018. Accordingly, $1.6 million in value related to the next milestone payment was recorded in accrued expenses and other current liabilities as of September 30, 2017, resulting in $7.2 million and $8.9 million being recorded in milestone rights liability and other liabilities, which is non-current, in the accompanying condensed consolidated balance sheets as of September 30, 2017 and December 31, 2016, respectively.

Accretion of debt issuance cost and debt discount in connection with the Facility Agreement during the three and nine months ended September 30, 2017 and 2016, which includes the acceleration of the debt discount and issuance costs related to the transactions disclosed above, are as follows (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2017		2016		2017		2016
Accretion expense - debt issuance cost	$	7	$	9	$	39	$	26
Accretion expense - debt discount	$	431	$	428	$	1,564	$	1,280

The Facility Agreement includes customary representations, warranties and covenants, including a restriction on the incurrence of additional indebtedness, and a financial covenant which requires the Company’s cash and cash equivalents on the last day of each fiscal quarter to not be less than $25.0 million, or pursuant to the Third Amendment, $10.0 million as of the last day of each month through October 31, 2017 and as of December 31, 2017 if certain conditions remained satisfied. As discussed in Note 1 – Description of Business and Summary of Significant Accounting Policies, the Company will need to raise additional capital to support its current operating plans. Due to the uncertainties related to maintaining sufficient resources to comply with the aforementioned covenant, the 2019 notes and Tranche B notes have been classified as current liabilities in the accompanying condensed consolidated balance sheets as of September 30, 2017 and December 31, 2016. In the event of non-compliance, Deerfield may declare all or any portion of the 2019 notes and/or Tranche B notes to be immediately due and payable.

Milestone Rights — The Milestone Agreement includes customary representations and warranties and covenants by the Company, including restrictions on transfers of intellectual property related to Afrezza. The Milestone Rights are subject to acceleration in the event the Company transfers its intellectual property related to Afrezza in violation of the terms of the Milestone Agreement. The Company has initially recorded the Milestone Rights at their estimated fair value.

Security Agreement — In connection with the Facility Agreement, the Company and its subsidiary, MannKind LLC, entered into a Guaranty and Security Agreement (the “Security Agreement”) with Deerfield and Horizon Santé FLML SÁRL (collectively, the “Purchasers”), pursuant to which the Company and MannKind LLC each granted the Purchasers a security interest in substantially all of their respective assets, including respective intellectual property, accounts receivables, equipment, general intangibles, inventory and investment property, and all of the proceeds and products of the foregoing. The Security Agreement includes customary covenants by the Company and MannKind LLC, remedies of the Purchasers and representations and warranties by the Company and MannKind LLC. The security interests granted by the Company and MannKind LLC will terminate upon repayment of the 2019 notes and Tranche B notes, if applicable, in full. The Company’s obligations under the Facility Agreement and the Milestone Agreement are also secured by the Company’s assets including property and equipment which have a carrying value of $27.4 million.

Embedded Derivatives — The Company identified and evaluated a number of embedded features in the notes issued under the Facility Agreement to determine if they represented embedded derivatives that are required to be separated from the notes and accounted for as freestanding instruments. The Company analyzed the Tranche B notes and identified embedded derivatives which required separate accounting. All of the embedded derivatives were determined to have a de minimis value as of September 30, 2017 and December 31, 2016.

Issuance of new 5.75% Convertible Senior Subordinated Exchange Notes Due 2018 in Exchange for 2015 Notes — As of September 30, 2017, the 5.75% Convertible Senior Subordinated Exchange Notes Due 2018 (the “2018 notes”) were the Company’s general, unsecured, senior obligations. Subsequently, on October 23, 2017, the 2018 notes were exchanged for new 5.75% Convertible Senior Subordinated Exchange Notes due 2021 (the “2021 notes”) and a specified number of shares of common stock as described in Note 15 – Subsequent Events. The 2018 notes ranked equally in right of payment with the Company’s other unsecured senior debt. The 2018 notes bore interest at the rate of 5.75% per year on the principal amount, payable semiannually in arrears in cash on February 15 and August 15 of each year, beginning February 15, 2016, with interest accruing from August 15, 2015. The 2018 notes would have matured on August 15, 2018. Accrued interest related to these notes is recorded in accrued expenses and other current liabilities on the accompanying condensed consolidated balance sheets.

The 2018 notes were convertible, at the option of the holder, at any time on or prior to the close of business on the business day immediately preceding the stated maturity date, into shares of the Company’s common stock at an initial conversion rate of 29 shares per $1,000 principal amount of 2018 notes, which was the initial conversion rate as defined in the agreement. The conversion rate was subject to adjustment under certain circumstances described in an indenture governing the 2018 notes dated August 10, 2015 with US Bank (as successor trustee to Wells Fargo, National Association), including in connection with a make-whole fundamental change. If certain fundamental changes had occurred, the Company would be obligated to pay a make-whole premium on any 2018 notes converted in connection with such fundamental change by increasing the conversion rate on such 2018 notes. If the Company underwent certain fundamental changes, except in certain circumstances, each holder of 2018 notes would have had the option to require the Company to repurchase all or any portion of that holder’s 2018 notes. The fundamental change repurchase price would have been 100% of the principal amount of the 2018 notes to be repurchased plus accrued and unpaid interest, if any.

On or after the date that is one year following the original issue date of the 2018 notes, the Company would have had the right to redeem for cash all or part of the 2018 notes if the last reported sale price of its common stock exceeds 130% of the conversion price then in effect for 20 or more trading days during the 30 consecutive trading day period ending on the trading day immediately prior to the date of the redemption notice. The redemption price was equal the sum of 100% of the principal amount of the 2018 notes to be redeemed, plus accrued and unpaid interest. Under the terms of the indenture, the conversion option could have been net-share settled and the maximum number of shares that could have been required to be delivered under the indenture, including the make-whole shares, was fixed and less than the number of authorized and unissued shares less the maximum number of shares that could have been required to be delivered during the term of the 2018 notes under existing commitments. Applying the Company’s sequencing policy, the Company performed an analysis at the time of the offering of the 2018 notes and each reporting date since and concluded that the number of available authorized shares at the time of the offering and each subsequent reporting date was sufficient to deliver the number of shares that could have been required to be delivered during the term of the 2018 notes under existing commitments.

The 2018 notes provided that upon an acceleration of certain indebtedness, including the 2019 notes and the Tranche B notes issued to Deerfield pursuant to the Facility Agreement, the holders may elect to accelerate the Company’s repayment obligations under the notes if such acceleration is not cured, waived, rescinded or annulled.

The Company incurred approximately $0.8 million in issuance costs, which are recorded as an offset to the 2018 notes, in the accompanying condensed consolidated balance sheets. These costs are being accreted to interest expense using the effective interest method over the term of the 2018 notes.

Amortization of the premium and accretion of debt issuance costs related to the 2018 notes for the three and nine months ended September 30, 2017 and 2016 are as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2017		2016		2017		2016
Amortization of debt premium	$	62	$	59	$	182	$	174
Accretion expense - debt issuance cost	$	70	$	65	$	204	$	190