FibroBiologics, Inc. (NASDAQ: FBLG) filed a 424B3 prospectus supplement registering 12,530,613 shares for resale — approximately 206% of the company's 6,080,560 shares currently outstanding. The shares stem from a $3.0 million at-the-market-priced private placement with Armistice Capital Master Fund Ltd., a hedge fund that frequently participates in structured financings for micro- and small-cap issuers.

Structure of the Placement

The deal carries several features that amplify its dilutive mechanics:

• Variable pricing with no floor. The placement was priced at market, meaning the per-share cost floats with the stock's trading price and contains no minimum price threshold.
• 200% warrant coverage. The transaction includes both short-term and long-term warrants exercisable at $0.735, a price that sits below the $0.8168 market price at the time of filing.
• Pre-funded warrants with nominal exercise price. A portion of the registered shares are tied to pre-funded warrants exercisable at $0.00001 per share — functionally equivalent to issued shares. These warrants are perpetual, carry no expiration date, and permit cashless exercise, meaning the holder can convert without injecting additional capital into the company.
• Beneficial ownership blockers. Armistice operates under a 9.99%/4.99% beneficial ownership limitation, which gates the pace at which shares can formally enter the float but does not reduce the total number of shares that may ultimately be issued.

Layered Overhang

The placement does not exist in isolation. FibroBiologics executed a 1-for-20 reverse stock split effective March 30, 2026, which compressed the outstanding share count. An April 2026 offering added roughly 2.27 million warrants that remain outstanding. The company also has a $7.5 million at-the-market (ATM) equity facility in place, providing a separate channel through which additional shares may be sold into the market over time.

Taken together, the 12.5 million registered resale shares represent approximately 67% of the fully diluted share count if all warrants and pre-funded warrants from this placement were exercised.

What the Filing Signals Structurally

The combination of variable-priced placement, no price floor, cashless-exercisable perpetual pre-funded warrants, and a counterparty known for structured financing creates a capital structure in which the share count can expand substantially without proportional cash inflows to the company. Pre-funded warrants at $0.00001 contribute virtually no exercise proceeds, and cashless exercise of standard warrants further limits future capital received per share issued.

The beneficial ownership blockers throttle the rate of conversion and sale but do not cap the aggregate dilution. Once blocker thresholds reset — through sales that reduce the holder's reported position — additional tranches of warrants can be exercised and shares sold.

The filing assigns a dilution risk score of 8 out of 10, reflecting the deep discount, variable pricing, absence of a floor, and the scale of registered shares relative to existing outstanding shares.