Debt

12 Months Ended

Dec. 31, 2025

Convertible Senior Notes Due 2029

On March 8, 2024, the Company completed an offering of $316.3 million aggregate principal amount of 1.50% Convertible Senior Notes due 2029 (the 2029 Notes). The proceeds from the issuance of the 2029 Notes were $306.8 million, net of debt issuance costs.

The Company used approximately $246.1 million of the net proceeds to repurchase approximately $246.7 million in aggregate principal amount of its Convertible Senior Notes Due 2025 (the 2025 Notes) concurrently with the pricing of the 2029 Notes in privately negotiated transactions. The Company also paid $1.3 million of accrued interest due at time of the note repurchase. As a result of the repurchase, the Company recognized a $1.3 million loss on extinguishment of debt in the consolidated statements of operations for the year ended December 31, 2024. The loss on extinguishment of debt included the unamortized debt issuance costs related to the portion of the 2025 Notes repurchased.

The Company also used $30.0 million of the net proceeds to repurchase shares of the Company’s common stock from certain purchasers of the 2029 Notes at a purchase price equal to the last reported sale price per share of the Company’s common stock on March 5, 2024, which was $27.105 per share. In addition, the Company used $15.8 million of the net proceeds to pay the cost of the capped call transactions (2029 Capped Call Transactions) discussed below.

The 2029 Notes are the Company’s senior unsecured obligations. Interest is payable in cash semi-annually in arrears on March 15 and September 15 of each year beginning on September 15, 2024, at a rate of 1.50% per year. The 2029 Notes mature on March 15, 2029 unless repurchased, redeemed, or converted in accordance with their terms before the maturity date.

The initial conversion rate for the 2029 Notes is 28.9361 shares of common stock per $1,000 principal amount of the 2029 Notes, which is equivalent to an initial conversion price of approximately $34.56 per share of the Company’s common stock (2029 Notes Conversion Price). The conversion rate is subject to customary adjustments for certain events as described in the indenture governing the 2029 Notes.

The Company may not redeem the 2029 Notes before March 22, 2027. The Company has the option to redeem for cash all or any portion of the 2029 Notes on or after March 22, 2027 if the last reported sale price of the Company’s common stock has been at least 130% of the 2029 Notes Conversion Price then in effect for at least 20 trading days (whether or not consecutive), including the trading day immediately preceding the date on which the Company provides notice of redemption, during any 30 consecutive trading day period, at a redemption price equal to 100% of the principal amount of the 2029 Notes to be redeemed, plus accrued and unpaid interest. No sinking fund is provided for the 2029 Notes.

Holders of the 2029 Notes may convert all or a portion of their 2029 Notes at their option before December 15, 2028, in multiples of $1,000 principal amounts, only under the following circumstances:

•during any calendar quarter commencing after the quarter ending on June 30, 2024 (and only during such calendar quarter), if the last reported sale price of the Company’s common stock, for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the 2029 Notes Conversion Price on each applicable trading day;

•during the five business day period after any ten consecutive trading day period (the measurement period) in which the trading price per $1,000 principal amount of the 2029 Notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price of the Company’s common stock and the applicable conversion rate of the 2029 Notes on such trading day;

•if the Company calls such 2029 Notes for redemption, at any time before the close of business on the scheduled trading day immediately preceding the redemption date, but only with respect to the 2029 Notes called (or deemed called) for redemption; or

•on the occurrence of specified corporate events.

On or after December 15, 2028, until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert their 2029 Notes, in integral multiples of $1,000 principal amount, at any time, regardless of the foregoing circumstances. Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of common stock, or a combination of cash and shares of common stock, at the Company’s election, in the manner and subject to the terms and conditions provided in the indenture governing the 2029 Notes.

Convertible Senior Notes Due 2025

In May 2020, the Company completed an offering of $287.5 million aggregate principal amount of 1.50% Convertible Senior Notes due 2025 (the 2025 Notes). The proceeds from the issuance of the Notes were $244.6 million, net of debt issuance costs and cash used to pay the cost of certain related capped call transactions. In March 2024, the Company repurchased for cash $246.7 million aggregate principal amount of the 2025 Notes, concurrently with the pricing of the 2029 Notes in privately negotiated transactions. The 2025 Notes matured in the second quarter of 2025, and the Company settled the balance of $40.8 million using existing cash balances.

The net carrying amount of the Company’s convertible senior notes on the consolidated balance sheets consisted of the following (in thousands):


	December 31, 2025		December 31, 2024
Principal amount:

Convertible Senior Notes Due 2029	$	316,250	$	316,250
Convertible Senior Notes Due 2025	—		40,760
Total principal amount	316,250		357,010
Unamortized debt issuance costs	(6,214)		(8,074)
Total debt, net	$	310,036	$	348,936
Less: current portion	—		(40,670)
Long-term senior convertible notes	$	310,036	$	308,266

As of December 31, 2025, the if-converted value of the 2029 Notes did not exceed the principal amount. As of December 31, 2024, the if-converted value of the 2029 Notes exceeded the principal amount by $13.4 million.

The following table summarizes the effective interest rates for each of our convertible senior notes for the periods shown:


	Year Ended December 31,
		2025		2024		2023
Effective interest rate:
Convertible Senior Notes Due 2025(1)		2.1	%	2.1	%	2.2	%
Convertible Senior Notes Due 2029		2.1	%	2.1	%	*

(1) The effective interest rate presented represents the rate applicable for the period outstanding. The 2025 Notes matured in May 2025, and the outstanding principal balance was settled using cash balances.

* Not applicable as no notes were outstanding at this date.

The following table details interest expense related to the Notes recognized for the years ended months ended December 31, 2025, 2024 and 2023 (in thousands):


	Year Ended December 31,
		2025		2024		2023
Contractual interest expense(1)		$	4,948	$	5,161	$	7,565
Amortization of debt issuance costs		1,860		1,906		1,803

Total interest expense		$	6,808	$	7,067	$	9,368

(1) Contractual interest expense for the year ended December 31, 2023 included $3.3 million of additional interest. In October 2023, the Company was notified that additional interest beyond the 1.50% per annum had been accruing on the 2025 Notes since May 2021, under the terms of the indenture. This additional interest accrued at a rate of 0.50% per annum on the outstanding principal amount of the Notes to approximately $3.3 million. The additional accrued interest was fully paid during the fourth quarter of 2023.

2029 Capped Call Transactions

In connection with the issuance of the 2029 Notes, the Company entered into Capped Call Transactions in March 2024 with certain counterparties at a net cost of $15.8 million (2029 Capped Call Transactions). The 2029 Capped Call Transactions are expected generally to reduce potential dilution to the Common Stock upon any conversion of the 2029 Notes and/or offset any cash payments the Company is required to make in excess of the principal amount of converted 2029 Notes, as the case may be, with such reduction and/or offset subject to a cap based on a cap price initially equal to $42.01 per share, and is subject to certain adjustments under the terms of the 2029 Capped Call Transactions.

Promissory Note Payable

In connection with the acquisition of Capillary Biomedical, Inc. in 2022, the Company assumed a $4.7 million promissory note payable. The promissory note accrues interest at the rate of 5.0% per year, and becomes due and payable upon the first sale or license of the commercialized product. As of December 31, 2025 and 2024, the loan balance, including accrued interest, was $4.9 million and $4.8 million, respectively, and was included as a component of other current liabilities on the consolidated balance sheets.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

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+ Details

TANDEM DIABETES CARE INC 10-K