12. Debt

MidCap Revolving Credit Facility

On June 14, 2017, the Company entered into a credit and security agreement (the "Credit Agreement") by and among the Company, as borrower, TomoTherapy Incorporated, a direct, wholly-owned subsidiary of the Company, as borrower ("TomoTherapy," and together with the Company, the "Borrowers"), any additional borrower that may be added thereto, MidCap Financial Trust ("MidCap"), individually as a lender and as agent ("Agent"), and the other lenders from time to time parties thereto (together with MidCap as a lender, the "Lenders"). The Credit Agreement provides for a revolving credit facility in the initial amount of $52.0 million, which the Company may request be increased by up to $33.0 million to a new total of $85.0 million through additional tranches, each with a $1.0 million minimum (the "Facility"). Neither Agent nor the Lenders have any obligation to consent to activation of an additional tranche. Availability for borrowings under the Facility is subject to a borrowing base that is calculated as a function of the value of the Borrowers' eligible accounts receivable and eligible inventory, and the Borrowers are required to maintain a minimum drawn balance of at least 30% of such availability.

The Facility's stated maturity date is June 14, 2021, but the Facility may mature earlier than the stated maturity date if certain conditions set forth in the Credit Agreement are not met, including conditions related to the Company's Existing 3.50% Convertible Notes maturing February 1, 2018.

The Borrowers' obligations under the Credit Agreement are secured by first-priority liens on substantially all the assets of the Borrowers, subject to certain exceptions.

Interest on the borrowings under the Facility is payable monthly in arrears at an annual interest rate of reserve-adjusted, 90-day LIBOR (subject to a 1.00% floor) plus 4.50%. The Credit Agreement requires the Borrowers to pay Agent a collateral management fee of 0.10% per month on the outstanding balance of the Facility. The Credit Agreement also requires the Borrowers to pay the Lenders an unused line fee equal to 0.5% per annum of the average unused portion of the Facility. If all or a portion of the Lenders' funding obligations under the Credit Agreement terminate for any reason other than as a result of a refinancing of 100% of the loans made under the Facility by Agent and the Lenders, then the Company will be required to pay a fee equal to 3% of the commitment amount terminated if such termination occurs within the first year, 2% of the commitment amount terminated if such termination occurs within the second year, and 1% of the commitment amount terminated if such termination occurs after the second year.

The Credit Agreement contains restrictions and covenants applicable to the Company and its subsidiaries. Among other requirements, the Company may not permit the Fixed Charge Coverage Ratio (as defined in the Credit Agreement) to be less than a certain specified ratio for each fiscal quarter during the term of the Facility.

The Credit Agreement also contains customary covenants that limit, among other things, the ability of the Company and its subsidiaries to (i) incur indebtedness, (ii) incur liens on their property, (iii) pay dividends or make other distributions, (iv) sell their assets, (v) make certain loans or investments, (vi) merge or consolidate, (vii) voluntarily repay or prepay certain indebtedness and (viii) enter into transactions with affiliates, in each case subject to certain exceptions. The Credit Agreement contains customary representations and warranties and events of default.

First Lien Senior Secured Term Loan due January 2021 (Secured Loan)

On January 11, 2016, the Company closed a $70.0 million first lien senior secured debt financing agreement with Cerberus Business Finance, LLC, an affiliate of Cerberus Capital Management, L.P (the "Secured Loan"). The proceeds of the loan were to be used to retire the 3.75% Convertible Notes at the earlier of August 2016 or when otherwise redeemed. The Secured Loan bore interest at a variable rate per annum equal to, at the Company's option, (i) the LIBOR Rate for one month plus an applicable margin of 7.00% (subject to a LIBOR Rate floor of 1.00% per annum), or (ii) a Reference Rate, which is the higher of 1) 3.25%, 2) Federal Funds Rate plus 0.5%, 3) the LIBOR rate for 1 month plus 1%, and 4) the US Prime Rate as published in the Wall Street Journal, plus an applicable margin of 4.75% per annum. The loan was repayable in consecutive quarterly installments of $875,000 with the final payment due on the final maturity date. The Secured Loan was to mature on the earlier of: (i) January 11, 2021 and (ii) the date that is 120 days prior to the scheduled maturity date of the 3.50% Convertible Notes maturing February 1, 2018 unless the Company had set aside specifically identifiable funds raised from new common equity or new debt equal to the then-outstanding principal amount of the 3.50% Convertible Notes. The net proceeds from the offering, after deducting the initial purchaser's discount and commission and the related offering costs, were approximately $65.5 million. The offering costs of $3.1 million and the initial purchaser's discount and commission of $1.4 million (both of which are recorded in Long-term Debt) were being amortized to interest expense using the effective interest method over five years. The Secured Loan is secured by first-priority liens on substantially all the assets of the Company.

The Company could, at its election, repay the Secured Loan at any time and if so, the Company would be required to pay a prepayment premium of 2% if the Secured Loan was repaid or accelerated within the first year on the amount repaid and 1% if the Secured Loan was repaid or accelerated within the second year on the amount repaid. In June 2017, the Company elected to repay the outstanding balance of the Secured Loan in the amount of $60.6 million plus accrued interest of $0.2 million and a prepayment premium of $0.6 million. The remaining offering costs and discount of approximately $2.2 million and $1.3 million, respectively, were charged to interest expense. Accordingly, the Secured Loan was terminated.

3.75% Convertible Senior Notes due August 2016

On August 1, 2011, the Company issued the 3.75% Convertible Notes to certain qualified institutional buyers or QIBs. The 3.75% Convertible Notes were offered and sold to the QIBs pursuant to Rule 144A under the Securities Act of 1933, as amended or Rule 144A. The net proceeds from the $100 million offering, after deducting the initial purchaser's discount and commission and the related offering costs, were approximately $96.1 million. The offering costs and the initial purchaser's discount and commission (which are recorded in Other Assets) were both being amortized to interest expense using the effective interest method over five years. The 3.75% Convertible Notes bore interest at a rate of 3.75% per year, payable semi-annually in arrears in cash on February 1 and August 1 of each year, beginning on February 1, 2012. The 3.75% Convertible Notes would mature on August 1, 2016, unless earlier repurchased, redeemed or converted.

The 3.75% Convertible Notes were issued under an Indenture between the Company and The Bank of New York Mellon Trust Company, N.A., as trustee. Holders of the 3.75% Convertible Notes could convert their 3.75% Convertible Notes at any time on or after May 1, 2016 until the close of business on the business day immediately preceding the maturity date. Prior to May 1, 2016, holders of the 3.75% Convertible Notes could convert their 3.75% Convertible Notes only under the following circumstances: (1) during any calendar quarter after the calendar quarter ending September 30, 2011, and only during such calendar quarter, if the closing sale price of the Company's common stock for each of 20 or more trading days in the 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter exceeds 130% of the conversion price in effect on the last trading day of the immediately preceding calendar quarter; (2) during the five consecutive business days immediately after any five consecutive trading-day period (such five consecutive trading-day period, the "Note Measurement Period") in which the trading price per $1,000 principal amount of 3.75% Convertible Notes for each trading day of that Note Measurement Period was equal to or less than 98% of the product of the closing sale price of shares of the Company's common stock and the applicable conversion rate for such trading day; (3) if the Company called any or all of the 3.75% Convertible Notes for redemption, at any time prior to the close of business on the business day immediately preceding the redemption date; or (4) upon the occurrence of specified corporate transactions as described in the Indenture. Upon conversion by holders of the 3.75% Convertible Notes, the Company would have the right to pay or deliver, as the case may be, cash, shares of common stock of the Company or a combination thereof, at the Company's election. At any time on or prior to the 33rd business day immediately preceding the maturity date, the Company could irrevocably elect to (a) deliver solely shares of common stock of the Company in respect of the Company's conversion obligation or (b) pay cash up to the aggregate principal amount of the 3.75% Convertible Notes to be converted and pay or deliver, as the case may be, cash, shares of common stock of the Company or a combination thereof in respect of the remainder, if any, of the Company's conversion obligation in excess of the aggregate principal amount of the 3.75% Convertible Notes being converted. The initial conversion rate was 105.5548 shares of the Company's common stock per $1,000 principal amount of 3.75% Convertible Notes (which represented an initial conversion price of approximately $9.47 per share of the Company's common stock). The conversion rate, and thus the conversion price, was subject to adjustment as further described below.

Holders of the 3.75% Convertible Notes who converted their 3.75% Convertible Notes in connection with a "make-whole fundamental change," as defined in the Indenture, could be entitled to a make-whole premium in the form of an increase in the conversion rate. Additionally, in the event of a "fundamental change," as defined in the Indenture, holders of the 3.75% Convertible Notes could require the Company to purchase all or a portion of their 3.75% Convertible Notes at a fundamental change repurchase price equal to 100% of the principal amount of 3.75% Convertible Notes, plus accrued and unpaid interest, if any, to, but not including, the fundamental change repurchase date.

Prior to the maturity date, the Company could redeem for cash all or a portion of the 3.75% Convertible Notes if the closing sale price of its common stock exceeded 130% of the applicable conversion price (the initial conversion price is approximately $9.47 per share of common stock) of such 3.75% Convertible Notes for at least 20 trading days during any consecutive 30 trading-day period (including the last trading day of such period).

In accordance with ASC 470-20, the Company separately accounted for the liability and equity conversion components of the 3.75% Convertible Notes. The principal amount of the liability component of the 3.75% Convertible Notes was $75.9 million as of the date of issuance based on the present value of its cash flows using a discount rate of 10%, our approximate borrowing rate at the date of the issuance for a similar debt instrument without the conversion feature. The carrying value of the equity conversion component was $24.1 million. A portion of the initial purchaser's discount and commission and the offering costs totaling $0.9 million was allocated to the equity conversion component. The liability component was being accreted to the principal amount of the 3.75% Convertible Notes using the effective interest method over five years.

In January 2016, the Company repurchased approximately $63.4 million in aggregate principal amount of its 3.75% Convertible Senior Notes due August 2016 for $66.6 million in cash. As $63.4 million of the 3.75% Convertible Senior Notes were settled in cash, a total of 6.7 million potentially dilutive shares were no longer potentially outstanding from a net loss per share perspective, these shares were already noted in Note 2 above as being excluded due to being anti-dilutive in the fiscal year 2016. The Company recorded a charge in the third quarter of fiscal 2016 of approximately $1.0 million associated with the repurchase of the notes. In August 2016, the Company settled the remaining 3.75% Convertible Senior Notes for approximately $36.6 million aggregate principal amount and $0.7 million accrued interest for approximately $37.3 million in cash.

3.50% Convertible Senior Notes due February 2018

In February 2013, the Company issued $115.0 million aggregate principal amount of its 3.50% Convertible Notes to certain QIBs. The 3.50% Convertible Notes were offered and sold to the QIBs pursuant to Rule 144A. The net proceeds from the offering, after deducting the initial purchaser's discount and commission and the related offering costs, were approximately $110.5 million. The offering costs and the initial purchaser's discount and commission (which are recorded in Other Assets) are both being amortized to interest expense using the effective interest method over five years. The 3.50% Convertible Notes bear interest at a rate of 3.50% per year, payable semi-annually in arrears in cash on February 1 and August 1 of each year, which began on August 1, 2013. The 3.50% Convertible Notes will mature on February 1, 2018, unless earlier repurchased, redeemed or converted.

In April 2014, through a series of transactions, the Company refinanced approximately $70.3 million aggregate principal amount of the 3.50% Convertible Notes with approximately $70.3 million aggregate principal amount of the Company's new 3.50% Series A Convertible Senior Notes due 2018 (the "3.50% Series A Convertible Notes").

The 3.50% Convertible Notes were issued under an Indenture between the Company and The Bank of New York Mellon Trust Company, N.A., as trustee. Holders of the 3.50% Convertible Notes may convert their 3.50% Convertible Notes at any time until the close of business on the business day immediately preceding the maturity date. The 3.50% Convertible Notes are convertible, as described below into common stock of the Company at an initial conversion rate equal to 187.6877 shares of common stock per $1,000 principal amount of the 3.50% Convertible Notes, which is equivalent to a conversion price of approximately $5.33 per share of common stock, subject to adjustment.

Holders of the 3.50% Convertible Notes who convert their 3.50% Convertible Notes in connection with a "make-whole fundamental change", as defined in the Indenture, may be entitled to a make-whole premium in the form of an increase in the conversion rate. Additionally, in the event of a "fundamental change," as defined in the Indenture, holders of the 3.50% Convertible Notes may require the Company to purchase all or a portion of their 3.50% Convertible Notes at a fundamental change repurchase price equal to 100% of the principal amount of 3.50% Convertible Notes, plus accrued and unpaid interest, if any, to, but not including, the fundamental change repurchase date.

In accordance with guidance in ASC 470-20, Debt with Conversion and Other Options and ASC 815-15, Embedded Derivatives, the Company determined that the embedded conversion components of the 3.50% Convertible Note do not require bifurcation and separate accounting. The remaining $44.7 million principal amount of the 3.50% Convertible Notes has been recorded in short-term debt on the consolidated balance sheet as of June 30, 2017.

3.50% Series A Convertible Senior Notes due February 2018

On April 17, 2014, the Company entered into note exchange agreements with certain holders (the "Participating Holders") of the 3.50% Convertible Notes to refinance approximately $70.3 million aggregate principal amount of the 3.50% Convertible Notes with approximately $70.3 million aggregate principal amount of the 3.50% Series A Convertible Notes. Pursuant to the note exchange agreements, the Company also paid the Participating Holders an aggregate of approximately $0.4 million in cash in connection with such transactions. The principal amount of 3.50% Convertible Notes refinanced for each $1,000 principal amount of the 3.50% Series A Convertible Notes was $1,000 and the amount in cash paid per $1,000 principal amount of such 3.50% Convertible Notes delivered was determined in individual negotiations between the Company and each Participating Holder. The Series A Convertible Notes have the same interest rate, maturity and other terms as the 3.50% Convertible Notes, except that the 3.50% Series A Convertible Notes are convertible into cash, shares of the Company's common stock or a combination of cash and shares of common stock, at the Company's option.

The 3.50% Series A Convertible Notes were issued under an Indenture between the Company and The Bank of New York Mellon Trust Company, N.A., as trustee. Holders of the 3.50% Series A Convertible Notes may convert their Securities at any time on or after November 1, 2017 until the close of business on the business day immediately preceding the maturity date. Prior to November 1, 2017, holders of the 3.50% Series A Convertible Notes may convert their Securities only under the following circumstances: (1) during any calendar quarter after the calendar quarter ending September 30, 2014, and only during such calendar quarter, if the closing sale price of the Company's common stock for each of 20 or more trading days in the 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter exceeds 130% of the conversion price in effect on the last trading day of the immediately preceding calendar quarter; (2) during the five consecutive business days immediately after any five consecutive trading-day period (such five consecutive trading-day period, the "Note Measurement Period") in which the trading price per $1,000 principal amount of 3.50% Series A Convertible Notes for each trading day of that Securities Measurement Period was equal to or less than 98% of the product of the closing sale price of shares of the Company's common stock and the applicable conversion rate for such trading day; or (3) upon the occurrence of specified corporate transactions as described in the Indenture. Upon conversion by holders of the 3.50% Series A Convertible Notes, the Company will have the right to pay or deliver, as the case may be, cash, shares of common stock of the Company or a combination thereof, at the Company's election. At any time on or prior to the 17th business day immediately preceding the maturity date, the Company may irrevocably elect to (a) deliver solely shares of common stock of the Company in respect of the Company's conversion obligation or (b) pay cash up to the aggregate principal amount of the 3.50% Series A Convertible Notes to be converted and pay or deliver, as the case may be, cash, shares of common stock of the Company or a combination thereof in respect of the remainder, if any, of the Company's conversion obligation in excess of the aggregate principal amount of the 3.50% Series A Convertible Notes being converted. The initial conversion rate is 187.6877 shares of the Company's common stock per $1,000 principal amount of 3.50% Series A Convertible Notes (which represents an initial conversion price of approximately $5.33 per share of the Company's common stock). The conversion rate, and thus the conversion price, is subject to adjustment as further described below.

Holders of the 3.50% Series A Convertible Notes who convert their Notes in connection with a "make-whole fundamental change", as defined in the Indenture, may be entitled to a make-whole premium in the form of an increase in the conversion rate. Additionally, in the event of a "fundamental change," as defined in the Indenture, holders of the 3.50% Series A Convertible Notes may require the Company to purchase all or a portion of their 3.50% Convertible Notes at a fundamental change repurchase price equal to 100% of the principal amount of the 3.50% Series A Convertible Notes, plus accrued and unpaid interest, if any, to, but not including, the fundamental change repurchase date.

In accordance with Accounting Standards Codification, or ASC 470-20, Debt with Conversion and Other Options, the Company separately accounts for the liability and equity conversion components of the 3.50% Series A Convertible Notes. The principal amount of the liability component of the 3.50% Series A Convertible Notes was $62.5 million as of the date of issuance based on the present value of its cash flows using a discount rate of 7%, our approximate borrowing rate at the date of the issuance for a similar debt instrument without the conversion feature. The carrying value of the equity conversion component was $7.9 million. In addition, the portion of the cash amount paid to the Participating Holders totaling $0.4 million was allocated to the debt discount with the remaining $47,000 to the equity component. The liability component is being accreted to the principal amount of the 3.50% Series A Convertible Notes using the effective interest method through the maturity in February 2018.

The following table presents the carrying values of all Convertible Notes and notes issued pursuant to the Revolving Credit Facility (collectively, "Notes") as of June 30, 2017 (in thousands):

	Revolving Loan		3.50% Convertible Notes			3.50% Series A Convertible Notes			Total
Carrying amount of equity conversion component	$	—	$	—		$	7,844		$	7,844


Principal amount of the Notes	$	51,548	$	44,654		$	70,346		$	166,548
Unamortized debt costs		—		(555	)		—			(555	)
Unamortized debt discount		—		—			(1,422	)		(1,422	)

Net carrying amount	$	51,548	$	44,099		$	68,924		$	164,571

As of June 30, 2017, the remaining period over which the unamortized debt discount of the of the 3.50% Series A Convertible Notes is 7 months using an effective interest rate of 7.10%.

A summary of interest expense on the Notes is as follows (in thousands):

	Year ended June 30,
	2017(1)		2016		2015
Interest expense related to contractual interest coupon	$	9,465	$	9,411	$	7,774
Interest expense related to amortization of debt discount		4,052		6,321		7,241
Interest expense related to amortization of debt issuance costs		3,785		1,728		1,503

Total	$	17,302	$	17,460	$	16,518


(1)	Debt issuance costs were higher in fiscal year 2017 due to the repayment of the Secured Loan and the write-off of the related debt issuance costs.