NovaBridge Biosciences (NBP) officer buys 230k shares at $2.51

Rhea-AI Filing Summary

NovaBridge Biosciences officer Mark Arnold Hagler reported an open-market purchase of 230,000 Ordinary Shares, represented by 100,000 American Depositary Shares (ADSs). The weighted average purchase price was $2.51 per ADS, with individual trades between $2.44 and $2.54. Following the transaction, he directly holds 230,000 Ordinary Shares.

Insider Trade Summary

Net Buyer: 230,000 shares ($577,300)

Net Buy 1 txn

Insider Hagler Mark Arnold

Role See Remarks

Bought 230,000 shs ($577K)

Type	Security	Shares	Price	Value
Purchase	Ordinary Shares	230,000	$2.51	$577K

Holdings After Transaction: Ordinary Shares — 230,000 shares (Direct, null)

Footnotes (1)

1. The Ordinary Shares may be represented by American Depositary Shares ("ADS"). Each 10 ADSs represent 23 Ordinary Shares of the Issuer. The reported securities are represented by 100,000 ADSs. The price reported in Column 4 is a weighted average price. These ADSs were purchased in multiple transactions at prices ranging from $2.44 to $2.54, inclusive. The Reporting Person undertakes to provide the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Key Figures

Ordinary Shares purchased: 230,000 shares ADSs purchased: 100,000 ADSs Weighted average price: $2.51 per ADS +3 more

6 metrics

Ordinary Shares purchased 230,000 shares Open-market purchase on 2026-04-24

ADSs purchased 100,000 ADSs Representing 230,000 Ordinary Shares

Weighted average price $2.51 per ADS Price reported for the purchase range

Price range $2.44–$2.54 per ADS Multiple trades within this range

Post-transaction holdings 230,000 Ordinary Shares Direct ownership after the transaction

ADS to Ordinary ratio 10 ADSs : 23 Ordinary Shares Structure of NovaBridge ADSs

Key Terms

American Depositary Shares, weighted average price, open-market purchase, Ordinary Shares

4 terms

American Depositary Shares financial

"The Ordinary Shares may be represented by American Depositary Shares ("ADS")."

American depositary shares (ADSs) are a way for investors in the United States to buy shares of foreign companies without dealing with international markets directly. They represent ownership in a foreign company's stock and are traded on U.S. stock exchanges, making it easier for American investors to buy, sell, and own parts of companies from around the world.

weighted average price financial

"The price reported in Column 4 is a weighted average price."

Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.

open-market purchase financial

"transaction_action": "open-market purchase""

An open-market purchase is when an investor or a company buys shares on a public stock exchange at the going market price, rather than through a private deal. It matters to investors because these purchases change how many shares are available, can push the stock price up or signal confidence from large buyers, and often affect per-share metrics like earnings—think of it like someone buying lots of apples off a grocery shelf, reducing supply and potentially raising the price.

Ordinary Shares financial

"The Ordinary Shares may be represented by American Depositary Shares"

Ordinary shares are a type of ownership stake in a company, giving shareholders a right to participate in the company’s profits and decision-making through voting. They are similar to owning a piece of a business, and their value can rise or fall based on the company's performance. Investors buy ordinary shares to potentially earn dividends and benefit from the company's growth over time.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

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:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Hagler Mark Arnold

(Last) (First) (Middle)

C/O NOVABRIDGE BIOSCIENCES,

2440 RESEARCH BOULEVARD, SUITE 400

(Street)

ROCKVILLE MARYLAND 20850

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
NovaBridge Biosciences [ NBP ]

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
04/24/2026

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

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

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

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Ordinary Shares(1)	04/24/2026		P		230,000(2)	A	$2.51(3)	230,000(2)	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. The Ordinary Shares may be represented by American Depositary Shares ("ADS"). Each 10 ADSs represent 23 Ordinary Shares of the Issuer.

2. The reported securities are represented by 100,000 ADSs.

3. The price reported in Column 4 is a weighted average price. These ADSs were purchased in multiple transactions at prices ranging from $2.44 to $2.54, inclusive. The Reporting Person undertakes to provide the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Remarks:

President and Chief Commercial Officer

	/s/ Xi-Yong (Sean) Fu as attorney-in-fact	04/28/2026
	** 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 4 (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 4: SEC 1474 (03-26)

FAQ

What insider transaction did NovaBridge Biosciences (NBP) report on this Form 4?

NovaBridge Biosciences reported that officer Mark Arnold Hagler made an open-market purchase of 230,000 Ordinary Shares, represented by 100,000 ADSs. This filing shows his direct ownership position after the transaction based on trades executed within a narrow price range.

How many NovaBridge Biosciences (NBP) shares did the insider buy and at what price?

The insider purchased 230,000 Ordinary Shares of NovaBridge Biosciences, represented by 100,000 ADSs. The weighted average purchase price was $2.51 per ADS, with individual trades completed between $2.44 and $2.54 across multiple open-market transactions.

What does the ADS structure mean for NovaBridge Biosciences (NBP) shareholders?

Each 10 American Depositary Shares of NovaBridge Biosciences represent 23 Ordinary Shares. In this transaction, the 100,000 ADSs correspond to 230,000 Ordinary Shares, clarifying how the U.S.-traded ADSs relate to the company’s underlying ordinary equity.

What is the insider’s ownership in NovaBridge Biosciences (NBP) after this transaction?

After this reported purchase, officer Mark Arnold Hagler holds 230,000 Ordinary Shares of NovaBridge Biosciences directly. The Form 4 shows this as his total direct position following the open-market ADS purchases disclosed in the filing.

Was the NovaBridge Biosciences (NBP) insider trade a market purchase or another type of transaction?

The filing classifies the activity as an open-market purchase. The transaction code is “P,” and the narrative description identifies it as a purchase in the open market or a private transaction, rather than an option exercise, grant, or gift.