Debt
The components of debt consisted of the following: 
 December 31, 2025December 31, 2024
(in millions)
Maturity Date
Amount
Effective Interest Rate
Amount
Effective Interest Rate
Equipment financing
2025$— — %$8.7 5.90 %
Mortgage
2025— — %60.9 5.74 %
Convertible Senior Notes
2026— — %800.0 0.76 %
Equipment financing202834.9 
4.27% - 10.44%
40.8 
4.27% - 8.87%
Revolving Credit Facility
2030— — %— — %
Term Loan B
2031477.5 7.05 %482.5 8.68 %
Senior Unsecured Notes
2033450.0 6.84 %— 
Unamortized debt discount2025 - 2033(3.5)(5.4)
Debt issuance costs2025 - 2033(9.7)(7.7)
Total debt, net949.2 1,379.8 
Less: current portion18.4 83.8 
Total long term-debt, net$930.8 $1,296.1 
Equipment Financings
The Company has outstanding loans secured by manufacturing lines located at the Company’s Acton, Massachusetts manufacturing facility.
Senior Secured Credit Agreement
The Company’s senior secured credit agreement (the “Credit Agreement”) includes a $500 million senior secured term loan B (the “Term Loan B”) and a senior secured revolving credit facility (“Revolving Credit Facility”). In March 2025, the Company upsized the borrowing capacity under its Revolving Credit Facility to $500 million and extended the maturity date to March 2030. In June 2025, the Company amended its Term Loan B to bear interest at a rate of Secured Overnight Financing Rate (“SOFR”) plus 2.00%. At the same time, the Company further amended its Revolving Credit Facility such that borrowings bear interest at a rate of SOFR plus an applicable margin of 1.50% to 2.00% based on the Company’s total leverage ratio.
In January 2024, the Company amended the Term Loan B to bear interest at a rate of SOFR plus 3.0%, with a 0% SOFR floor. In August 2024, the Company further amended its Term Loan B to bear interest at a rate of SOFR plus 2.5% and extended the term to August 2031.
The Term Loan B contains leverage and fixed charge coverage ratio covenants, both of which are measured upon the incurrence of future debt. The Revolving Credit Facility contains a covenant to maintain a specified leverage ratio under certain conditions when there are amounts outstanding.
Borrowings under the Credit Agreement are guaranteed by certain wholly owned domestic subsidiaries of the Company and are secured by substantially all assets of the Company and of each subsidiary guarantor, subject to certain exceptions. Additionally, borrowings under the Credit Agreement are senior to all of the Company’s unsecured indebtedness.
Senior Unsecured Notes
In March 2025, the Company issued $450 million aggregate principal amount of 6.5% senior unsecured notes due April 2033. The net proceeds of $440.7 million were used to repurchase a portion of the Convertible Senior Notes. The senior unsecured notes contains leverage and fixed charge coverage ratio covenants, both of which are measured upon the incurrence of future debt, as well as other customary covenants.
Convertible Senior Notes
In 2025, the Company repurchased $419.9 million aggregate principal amount ($417.6 million net of issuance costs) of 0.375% Convertible Senior Notes due September 2026 (the “Convertible Senior Notes”) for $541.5 million in cash, which resulted in a $123.9 million loss on extinguishment. The Company subsequently paid $510.7 million to redeem the remaining Convertible Senior Notes. The difference between this cash paid and the $380.1 million aggregate principal amount ($378.4 million net of issuance costs) redeemed resulted in a $132.3 million decrease to additional paid in capital. In connection with these transactions, the Company received $164.6 million of proceeds from the settlement of capped calls options associated with the Convertible Senior Notes.
As of December 31, 2024 unamortized issuance costs associated with the Convertible Senior Notes were $5.1 million.
The components of interest expense related to the Convertible Senior Notes were as follows:
Years Ended December 31,
(in millions)
202520242023
Contractual interest expense
$1.4 $3.0 $3.0 
Amortization of debt issuance costs
1.2 3.0 3.0 
Total interest recognized on the Convertible Senior Notes
$2.6 $6.0 $6.0 
Carrying Value
The carrying value amounts of the Company’s debt were as follows:
As of December 31,
(in millions)20252024
Mortgage$— $60.6 
Convertible Senior Notes— 794.9 
Equipment financings34.8 49.3 
Term Loan B473.0 475.1 
Senior Unsecured Notes441.4 — 
Total debt, net$949.2 $1,379.8 
Maturity of Debt
The maturity of debt as of December 31, 2025 is as follows:
Years Ending December 31, (in millions)
2026$18.4 
2027$19.4 
2028$12.1 
2029$5.0 
2030$5.0 

Historical Timeline

Fiscal YearFiled
2025Feb 18, 2026Showing above
2024Feb 21, 2025
2023Feb 23, 2024
2022Feb 24, 2023
2021Feb 24, 2022
2020Feb 24, 2021
2019Feb 26, 2020
2018Feb 26, 2019
2017Feb 22, 2018
2016Feb 28, 2017
2015Feb 29, 2016

About Debt Disclosures

Debt disclosures detail a company's borrowing structure — the types of instruments, interest rates, maturity schedule, and covenant restrictions that define its financial obligations and flexibility. This section is essential for assessing refinancing risk, interest rate exposure, and the margin of safety against financial distress.

Key signals: the maturity schedule reveals concentration risk — large maturities within 1-2 years during tight credit markets can force dilutive refinancing or asset sales. Compare the fair value of debt against carrying amount to gauge whether the market views the company's credit risk differently than the balance sheet suggests. Watch covenant compliance disclosures for tightening cushions, especially leverage and interest coverage ratios. Variable-rate debt exposure quantifies sensitivity to interest rate changes. Secured versus unsecured mix affects recovery rates and future borrowing capacity. Compare net debt-to-EBITDA against industry peers and covenant limits to assess financial health.