Convertible debt (Notes)

3 Months Ended

Mar. 31, 2024

Convertible Senior Notes

The following is a summary of the Company's convertible senior notes as of March 31, 2024 (in thousands):


	Date of Issuance	Unpaid Principal Balance		Contractual Interest Rates



1% Convertible Notes due in 2024 ("2024 Notes")	May 2019	$	21,713		1%
2.25% Convertible Notes due in 2027 ("2027 Notes")	September 2020 and October 2023	$	266,816		2.25%
Total Notes		$	288,529

The 2027 and 2024 Notes (collectively, the "Notes") are general unsecured obligations and rank senior in right of payment to all of the Company's indebtedness that is expressly subordinated in right of payment to the Notes, rank equally in right of payment with all of the Company's existing and future liabilities that are not so subordinated, are effectively junior to any of the Company's secured indebtedness to the extent of the value of the assets securing such indebtedness and are structurally subordinated to all indebtedness and other liabilities of the Company's subsidiaries (including trade payables but excluding intercompany obligations owed to the Company or its subsidiaries).

Interest related to the 2027 Notes is payable semi-annually in arrears in cash on March 15 and September 15 of each year, beginning on March 15, 2021. Interest related to the 2024 Notes is payable semi-annually in arrears on May 15 and November 15 of each year, beginning on November 15, 2019.

The 2027 Notes mature on September 15, 2027 and the 2024 Notes mature on May 15, 2024, unless redeemed or converted in accordance with their terms prior to such date.

Each $1,000 of principal of the 2027 Notes will initially be convertible into 23.9137 shares of the Company’s common stock, which is equivalent to an initial conversion price of approximately $41.82 per share. Each $1,000 of principal of the 2024

Notes will initially be convertible into 15.1394 shares of the Company’s common stock, which is equivalent to an initial conversion price of approximately $66.05 per share. The initial conversion price for the 2027 and the 2024 Notes is subject to adjustment upon the occurrence of certain specified events.

On August 23, 2023, the Company entered into legally binding exchange agreements with a limited number of existing holders of the 2024 Notes to exchange approximately $122.0 million aggregate principal amount of the existing 2024 Notes for a principal amount of the 2027 Notes at an exchange ratio to be determined based on the daily volume-weighted average trading price of the Company’s common stock over a thirty-day trading period beginning August 24, 2023 (such exchange transactions, the “Exchange”). On October 10, 2023, the Company settled the exchange agreements for the exchange of $122.0 million aggregate principal amount of its outstanding 2024 Notes for newly issued $116.8 million aggregate principal amount of its outstanding 2027 Notes. Following the settlement of the Exchange, $21.7 million in aggregate principal amount of the 2024 Notes and $266.8 million in aggregate principal amount of the 2027 Notes remain outstanding with terms unchanged. The 2027 Notes issued in the Exchange constitute a further issuance of, and form a single series and will be fungible with, the existing 2027 Notes.

As of March 31, 2024, the 2027 and 2024 Notes are not yet convertible and their remaining term is approximately 42 months and 2 months, respectively.

As of March 31, 2024 and December 31, 2023, the fair value of the principal amount of the Notes in the aggregate was $310.7 million and $320.5 million, respectively. The estimated fair value was determined based on inputs that are observable in the market or that could be derived from, or corroborated with, observable market data, including the Company's stock price and interest rates, which represents level 2 in the fair value hierarchy.

The Notes consist of the following (in thousands):


	March 31, 2024		December 31, 2023

Principal	$	288,529	$	288,529
Debt premium, net of amortization	9,100		9,776
Debt issuance costs, net of amortization	(3,990)		(4,313)
Net carrying amount	$	293,639	$	293,992

The following table sets forth total interest expense recognized related to the Notes (in thousands):


	Three Months Ended March 31,
		2024		2023
Coupon interest		$	1,555	$	1,203
Amortization of debt issuance costs		323		373
Amortization of debt premium		(676)		—
Total		$	1,202	$	1,576

Capped call transactions

In September 2020 and in May 2019, in connection with the offering of the 2027 and 2024 Notes, respectively, the Company entered into privately negotiated capped call transactions (collectively, the "Capped Call") with certain option counterparties. The Capped Call transactions cover, subject to customary anti-dilution adjustments, the number of shares of the Company’s common stock initially underlying the Notes, at a strike price that corresponds to the initial conversion price of the Notes, also subject to adjustment, and are exercisable upon conversion of the Notes. The Capped Call transactions are intended to reduce potential dilution to the Company’s common stock and/or offset any cash payments the Company will be required to make in excess of the principal amounts upon any conversion of the Notes, and to effectively increase the overall conversion price of the 2027 Notes from $41.82 to $78.90 per share, and for the 2024 Notes from $66.05 to $101.62 per share. As the Capped Call transactions meet certain accounting criteria, they are recorded in stockholders’ (deficit) equity and are not accounted for as derivatives. The cost of the Capped Call was $25.3 million and $16.4 million for the 2027 and 2024 Notes, respectively, and was recorded as part of additional paid-in capital.

In August 2023, in connection with the Exchange, the Company entered into additional capped call transactions (the “Additional Capped Call”) with certain option counterparties. The Company agreed to pay a premium to the option

counterparties for the Additional Capped Call for an amount to be determined based on the volume-weighted average trading price of the Company’s common stock over a thirty-day reference period beginning August 24, 2023. The conversion price of the Additional Capped Call is the same as the 2027 Notes Capped Call above. Initial funding of the Additional Capped Call occurred in the third quarter of 2023. The Additional Capped Call had a deferred premium component indexed to the Company's stock price and required to be settled in cash, and therefore the Additional Capped Call was a derivative instrument that, at inception, did not meet the qualifications for equity classification. On October 10, 2023, the Company settled the deferred premium on the Additional Capped Call resulting in a final value of $22.2 million. Once the deferred premium was settled, the instrument met the requirements for equity classification and the Company reclassified the Additional Capped Call to additional paid-in capital.