Every 424B that Merck & Co., Inc. (MRK) has filed with the SEC in the last 12 months is listed below, newest first, and each one links through to the document itself with the summary and the scores our analysis gives it.
A 424B covers the supplement that carries the terms of a priced offering, so if you follow MRK and want that one kind of document rather than the whole filing history, this is the page to keep. The company's other filings, of every form, are on the full MRK filings page.
Merck & Co., Inc. is offering $6,000,000,000 of unsecured senior notes across seven series comprising floating-rate and fixed-rate maturities from May 22, 2028 through May 22, 2056. The prospectus supplement states net proceeds, estimated at approximately $5.96 billion, will be used to repay in full borrowings under a 364‑day delayed draw term loan credit agreement incurred to finance the acquisition of Terns Pharmaceuticals, Inc.
The offering lists series sizes and coupons explicitly (for example, $1.5 billion 5.200% notes due 2036 and $500 million floating‑rate notes due 2028), interest payment dates, optional redemption mechanics for fixed rate series and that the floating rate notes use Compounded SOFR + 0.370% (subject to benchmark‑replacement provisions). The notes will be unsecured, rank equally with other unsecured indebtedness and are not listed on an exchange.
Merck & Co., Inc. proposes a multi‑series debt offering of unsecured senior notes, including a floating‑rate series tied to Compounded SOFR and several fixed‑rate series, to be issued in minimum denominations of $2,000. Net proceeds are intended to repay borrowings under a 364‑Day Delayed Draw Term Loan Credit Agreement entered to finance the acquisition of Terns Pharmaceuticals, Inc., which closed on May 5, 2026. The prospectus supplement discloses the Terns acquisition consideration of $53.00 per share for an approximate equity value of $6.7 billion, and states the notes will rank equally with other unsecured senior indebtedness and be structurally subordinated to subsidiaries’ liabilities.
Merck & Co., Inc. is issuing $8.0 billion of senior unsecured notes across eight tranches, including a $500 million SOFR-linked floating-rate note due 2029 and fixed-rate notes maturing between 2029 and 2065 with coupons from 3.850% to 5.700%. The company expects net proceeds of about $7.92 billion.
Merck plans to use the cash for general corporate purposes, repayment of debt and potentially to help fund its proposed $9.2 billion cash acquisition of Cidara Therapeutics at $221.50 per share, centered on flu candidate CD388. If the Cidara deal is not completed by a specified end date or is terminated, several series of notes must be redeemed at 101% of principal plus interest.
The notes rank equally with Merck’s other senior unsecured debt and are structurally subordinated to subsidiary obligations. The offering increases total debt from $41.4 billion to $49.4 billion, while the floating-rate tranche exposes holders to SOFR-related benchmark and liquidity risks described in detail.
Merck & Co., Inc. is launching a multi-tranche senior notes offering, including floating-rate notes linked to Compounded SOFR and several fixed-rate series, to raise capital for general corporate purposes. The company may also use part of the proceeds to help fund its proposed all-cash acquisition of Cidara Therapeutics for $221.50 per share, valuing the transaction at about $9.2 billion.
The notes will be unsecured senior obligations of Merck, structurally subordinated to debt at its subsidiaries, and will not be listed on any exchange. Several series, including the floating-rate notes, carry a special mandatory redemption at 101% of principal plus accrued interest if the Cidara deal is not completed by the contractual deadline, the merger agreement is terminated, or Merck elects not to pursue the transaction. The filing also details risks tied to SOFR-based interest calculations, potential benchmark transitions, and the absence of an assured trading market for the notes.