Here are the S-3 shelf registrations from MBX Biosciences, Inc. (MBX) in our archive over the last 12 months, newest first, and each one links through to the document itself with the summary and the scores our analysis gives it.
An S-3 covers the shelf registration that lets an established company sell over time, so if you follow MBX 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 MBX filings page.
MBX Biosciences, Inc. filed a Form S-3 shelf registration that includes a sales agreement prospectus supplement to sell up to $250,000,000 of common stock from time to time under an Open Market Sale agreement with Jefferies LLC.
The registration statement establishes a base prospectus permitting the company to offer various securities (common stock, preferred stock, debt, warrants and units) on a continuous or delayed basis under separate prospectus supplements. The sales agreement supplement governs the mechanics of at‑the‑market offerings under the Jefferies arrangement and sales may commence from time to time after the effective date.
MBX Biosciences filed an S-3 shelf registration to offer, issue and sell up to $400,000,000 of securities from time to time. The filing also includes a sales agreement prospectus supplement for an at-the-market program to sell up to $150,000,000 of common stock through Jefferies LLC, which is included within the $400,000,000 shelf capacity.
Sales may occur on a continuous or delayed basis, with specific terms set in future supplements. The company states that net proceeds will be used for development of clinical-stage programs, discovery R&D, additional clinical development, and general corporate purposes, including working capital and capital expenditures.
MBX’s common stock trades on the Nasdaq Global Select Market under “MBX.” The last reported sale price was $20.62 per share on November 4, 2025. Shares outstanding were 44,715,498 as of September 30, 2025.