In June 2020, the Company issued $400 million aggregate principal amount of 0.375% convertible senior notes due June 1, 2025 (the “2025 Notes”) in a private offering and an additional $60 million aggregate principal amount of the 2025 Notes pursuant to the exercise in full of the over-allotment options of the initial purchasers. The interest rate is fixed at 0.375% per annum and is payable semi-annually in arrears on June 1 and December 1 of each year. The total net proceeds from the debt offering, after deducting initial purchase discounts and debt issuance costs, were approximately $450.1 million.

Each $1,000 of principal amount of the 2025 Notes will initially be convertible into 3.5396 shares of the Company’s common stock (the “Conversion Option of the 2025 Notes”), which is equivalent to an initial conversion price of approximately $282.52 per share, subject to adjustment upon the occurrence of certain specified events. On or after March 1, 2025 until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert their 2025 Notes at any time. The 2025 Notes will be convertible at the option of the holders prior to the close of business on the business day immediately preceding March 1, 2025 under certain circumstances as described in the indenture governing the 2025 Notes (the “Indenture”). Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of the Company’s common stock or a combination of cash and shares of the Company’s common stock, at the Company’s election. The Company expects to settle the principal amount of the 2025 Notes in cash. Because the last reported sale price of the Company’s common stock for at least 20 trading days during the period of 30 consecutive trading days ending on the last trading day of the calendar quarter ended December 31, 2024 was equal to or greater than 130% of the applicable conversion price on each applicable trading day, the 2025 Notes are convertible at the option of the holders thereof during the calendar quarter ending March 31, 2025.

The net carrying amount of the liability component of the 2025 Notes is as follows:


	As of December 31, 2024			As of December 31, 2023
	(in thousands)
Principal	$	459,048		$	459,076
Unamortized issuance costs		(864	)		(2,870	)
Net carrying amount	$	458,184		$	456,206

Interest expense related to the 2025 Notes is as follows:


	Year Ended December 31,
	2024		2023		2022
	(in thousands)
Contractual interest expense	$	1,722	$	1,722	$	1,722
Amortization of issuance costs		2,012		1,986		1,969
Total interest expense	$	3,734	$	3,708	$	3,691

In connection with the offering of the 2025 Notes, the Company purchased capped call options (“Capped Call Options”) with respect to its common stock for $50.6 million. The Capped Call Options are purchased call options that give the Company the option to purchase up to approximately 1.6 million shares of its common stock for $282.52 per share, which corresponds to the approximate initial conversion price of the 2025 Notes. The Capped Call Options were purchased in order to offset potential dilution to the Company’s common stock upon any conversion of the 2025 Notes, subject to a cap of $426.44 per share, and expire concurrently with the 2025 Notes. The Capped Call Options automatically settle in components commencing on April 16, 2025 and are subject to either adjustment or termination upon the occurrence of specified extraordinary events affecting the Company, including a merger event; a tender offer; and a nationalization, insolvency or delisting involving the Company. In addition, the Capped Call Options are subject to certain specified additional disruption events that may give rise to a termination of the Capped Call Options, including changes in law, insolvency filings, and hedging disruptions. Since the transaction meets certain accounting criteria, the $50.6 million paid for the Capped Call Options is recorded in stockholders’ equity as a reduction in additional paid-in capital and are not accounted for as separate derivative financial instruments.