LeonaBio reports 10% holder with 5.5M $0.001 warrant

David J. Portman reports indirect voting control over a large, non-expiring warrant position in LeonaBio common stock via Sermonix Pharmaceuticals.

Rhea-AI Filing Summary

LeonaBio, Inc. (LONA) reports that David J. Portman is a ten percent owner and discloses his indirect control over a large warrant position. The filing lists an indirectly held warrant for 5,502,402 shares of LeonaBio common stock, exercisable at $0.001 per share with no expiration.

The warrant is held by Sermonix Pharmaceuticals, Inc., where Mr. Portman is Chief Executive Officer, and the filing states it is being made to report his voting control over these securities. It also states that his personal indirect beneficial ownership does not exceed ten percent of LeonaBio’s stock.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Portman David J.

Role 10% Owner

Type	Security	Shares	Price	Value
holding	Warrant F2, F1	--	--	--

Holdings After Transaction: Warrant — 5,502,402 contracts (Indirect, See note)

Footnotes (2)

1. F1. The warrant is held by Sermonix Pharmaceuticals, Inc., of which Mr. Portman is the Chief Executive Officer. This Form 3 is being filed to report Mr. Portman's voting control over such securities, but Mr. Portman's personal indirect beneficial ownership does not exceed 10% of the stock in the issuer.
2. F2. The warrant does not expire.

Key Figures

Underlying common shares: 5,502,402 shares Warrant exercise price: $0.001 per share Ownership type: Indirect

3 metrics

Underlying common shares 5,502,402 shares Underlying security shares linked to the indirectly held warrant

Warrant exercise price $0.001 per share Exercise price for the warrant on LeonaBio common stock

Ownership type Indirect Warrant is held through Sermonix Pharmaceuticals, Inc.

Key Terms

Warrant, voting control, beneficial ownership, ten percent owner

4 terms

Warrant financial

"The filing lists an indirectly held warrant for 5,502,402 shares"

A warrant is a time-limited financial contract that gives its holder the right to buy a company's shares at a set price before a specified date, like a coupon that lets you purchase stock at a fixed discount for a limited time. It matters to investors because warrants offer leveraged exposure to a stock’s upside and can dilute existing shareholders if exercised, so they affect potential gains and the company’s outstanding share count.

voting control financial

"filed to report Mr. Portman's voting control over such securities"

beneficial ownership financial

"Mr. Portman's personal indirect beneficial ownership does not exceed 10%"

Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.

ten percent owner regulatory

"Mr. Portman is reported as a ten percent owner of LeonaBio, Inc."

FAQ

What insider position in LeonaBio (LONA) does David J. Portman report on this Form 3?

David J. Portman is reported as a ten percent owner of LeonaBio, Inc. The filing is made to report his voting control over certain warrant securities held by Sermonix Pharmaceuticals, Inc.

How many LeonaBio (LONA) shares are covered by the reported warrant?

The warrant reported for LeonaBio (LONA) covers 5,502,402 underlying shares of common stock. This figure reflects the underlying security shares tied to the indirectly held warrant position.

What is the exercise price of the warrant reported for LeonaBio (LONA)?

The warrant related to LeonaBio (LONA) common stock has an exercise price of $0.001 per share. This very low exercise price applies to the 5,502,402 underlying common shares referenced in the filing.

Does the reported warrant in LeonaBio (LONA) have an expiration date?

No. A footnote states that the warrant does not expire. This means the warrant for 5,502,402 underlying LeonaBio common shares is described as non-expiring in the filing.

How is David J. Portman’s interest in LeonaBio (LONA) held according to the Form 3?

The warrant is held indirectly through Sermonix Pharmaceuticals, Inc., where Mr. Portman is Chief Executive Officer. The filing notes his voting control over the securities, while stating that his personal indirect beneficial ownership does not exceed ten percent of LeonaBio’s stock.

Does the Form 3 for LeonaBio (LONA) report any recent insider purchases or sales?

No insider purchases or sales are reported. The Form 3 describes an existing indirect warrant holding for 5,502,402 underlying LeonaBio common shares, rather than new buy or sell transactions.

AI-generated analysis. How Rhea-AI works. Not financial advice.

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Available on EDGAR 09/03/2026 - 03:38 PM Accepted by SEC EDGAR 09/03/2026 - 03:38 PM Learn about SEC filing dates

SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0104
Estimated average burden
hours per response:			0.5

1. Name and Address of Reporting Person^*

Portman David J.

(Last) (First) (Middle)

250 E. BROAD ST., SUITE 250

(Street)

COLUMBUS OHIO 43215

(City) (State) (Zip)

UNITED STATES

(Country)

2. Date of Event Requiring Statement (Month/Day/Year)
08/24/2026

3. Issuer Name and Ticker or Trading Symbol
LeonaBio, Inc. [ LONA ]

3a. Foreign Trading Symbol

5. If Amendment, Date of Original Filed (Month/Day/Year)

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Warrant	10/26/2026	(2)	Common Stock	5,502,402	$0.001	I	See note(1)

Explanation of Responses:

1. The warrant is held by Sermonix Pharmaceuticals, Inc., of which Mr. Portman is the Chief Executive Officer. This Form 3 is being filed to report Mr. Portman's voting control over such securities, but Mr. Portman's personal indirect beneficial ownership does not exceed 10% of the stock in the issuer.

2. The warrant does not expire.

	/s/ David Portman	09/03/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 3: SEC 1473 (03-26)