Zenas BioPharma (ZBIO) holder sells 673,755 shares in open-market trade

Rhea-AI Filing Summary

Zenas BioPharma, Inc. (ZBIO) received an amended Schedule 13D/A from Enavate Sciences GP, LLC and Zebra Aggregator entities updating their ownership in the company’s common stock. The filing reports that Zebra LP directly holds 3,245,404 shares of Zenas common stock, over which Enavate GP shares voting and investment authority.

Based on 65,176,723 Zenas shares outstanding as of July 31, 2026, the reporting group beneficially owns 4.98% of the company’s common stock, which EDGAR displays as 4.9% due to rounding. On August 19, 2026, Zebra LP executed an open market sale of 673,755 shares at a weighted average price of $31.44 per share, within a range of $31.05–$32.00. As a result, the reporting persons state that they ceased to be beneficial owners of more than five percent of Zenas’ common stock on August 19, 2026.

Key Figures

Shares beneficially owned: 3,245,404 shares Beneficial ownership percentage: 4.98% Shares outstanding: 65,176,723 shares +4 more

7 metrics

Shares beneficially owned 3,245,404 shares Zebra LP common shares of Zenas BioPharma held as of the amendment

Beneficial ownership percentage 4.98% Portion of Zenas BioPharma common stock owned by the reporting group

Shares outstanding 65,176,723 shares Zenas BioPharma common stock outstanding as of July 31, 2026

Shares sold 673,755 shares Open market sale by Zebra LP on August 19, 2026

Weighted average sale price $31.44 per share Average price for Zebra LP’s August 19, 2026 open market sale

Sale price range $31.05–$32.00 per share Low and high prices for trades on August 19, 2026

Rounded EDGAR ownership 4.9% Ownership percentage shown in Row 13 due to EDGAR rounding

Key Terms

beneficially owns, Schedule 13D, dispositive power, voting power, +1 more

5 terms

beneficially owns financial

"each Reporting Person beneficially owns 4.98% of the outstanding Common Stock"

Beneficially owns means a person or entity enjoys the economic benefits and control of a security even if the legal title or registration is held in another name. Think of it like having the keys and profits from a car that is registered to a friend: you use it, benefit from it, and make decisions about it even though the official paperwork lists someone else. For investors, this matters because it reveals who truly controls shares, affects voting power, potential conflicts of interest, and regulatory disclosure obligations.

Schedule 13D regulatory

"amends and supplements the statement on originally filed on Schedule 13D"

A Schedule 13D is a legal document that investors file with regulators when they buy a large enough stake in a company to potentially influence its management or decisions. It provides details about the investor’s intention, ownership stake, and plans, helping other investors understand who is gaining control and what their motives might be.

dispositive power financial

"sole or shared power to dispose or to direct the disposition"

Dispositive power is the authority to decide the final outcome of an asset, legal claim, contract, or corporate action — in effect the power to dispose of or resolve something. For investors it matters because whoever holds that authority can determine who gets paid, who controls an asset or vote, and how risks and returns are allocated; think of it like holding the key that lets you lock in the winner or loser in a deal.

voting power financial

"sole or shared power to vote or direct the vote"

Voting power is the ability shareholders have to influence a company's major decisions—like electing the board, approving mergers, or changing corporate rules—based on the voting rights attached to the shares they hold. For investors it matters because greater voting power is like holding more keys to a building: it gives you a stronger say over management choices and the company’s strategy, which can affect future value and risk.

beneficial owners of more than five percent regulatory

"ceased to be the beneficial owners of more than five percent"

FAQ

What percentage of Zenas BioPharma (ZBIO) does the Enavate/Zebra group now own?

The reporting group beneficially owns 4.98% of Zenas BioPharma’s common stock. This percentage is based on 65,176,723 shares outstanding as of July 31, 2026, as disclosed in Zenas’ Form 10-Q filed on August 13, 2026.

How many Zenas BioPharma (ZBIO) shares does Zebra LP directly hold?

Zebra LP directly holds 3,245,404 shares of Zenas BioPharma common stock. Enavate Sciences GP, LLC is the general partner of Zebra LP and shares voting and investment authority over these shares according to the Schedule 13D/A amendment.

When did the Enavate/Zebra group fall below 5% ownership of Zenas BioPharma (ZBIO)?

The reporting persons state they ceased to be beneficial owners of more than 5% of Zenas BioPharma’s common stock on August 19, 2026. This ownership change is tied to an open market sale disclosed in the amended Schedule 13D/A.

What Zenas BioPharma (ZBIO) share sale did Zebra LP report on August 19, 2026?

Zebra LP reported an open market sale of 673,755 Zenas BioPharma shares on August 19, 2026. The weighted average sale price was $31.44 per share, with individual trades executed between $31.05 and $32.00 per share.

What share count did Zenas BioPharma (ZBIO) report as outstanding for the ownership calculation?

The ownership percentages are calculated using 65,176,723 Zenas BioPharma common shares outstanding. This figure comes from Zenas’ Quarterly Report on Form 10-Q for the period referenced, filed with the SEC on August 13, 2026.

Why does the Schedule 13D/A for Zenas BioPharma (ZBIO) show 4.9% when the text says 4.98%?

The reporting group states their beneficial ownership is 4.98%, but Row 13 of the cover pages shows 4.9% due to EDGAR field limitations. The percentage in the cover section is rounded down in the SEC’s electronic system.

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

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

Available on EDGAR 08/19/2026 - 06:50 PM Accepted by SEC EDGAR 08/19/2026 - 06:49 PM Learn about SEC filing dates

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 2)

Zenas BioPharma, Inc.

(Name of Issuer)

Common Stock, par value $0.0001 per share

(Title of Class of Securities)

98937L105

(CUSIP Number)

James P. Boylan
Enavate Sciences, 106 W 56th Street, 8th Floor
New York, NY, 10019
(332) 275-5551

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

08/19/2026

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

schemaVersion:

SCHEDULE 13D

CUSIP Number(s): 98937L105

1

Name of reporting person

Enavate Sciences GP, LLC

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

AF

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 3,245,404.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 3,245,404.00

11

Aggregate amount beneficially owned by each reporting person

3,245,404.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

4.9 %

14

Type of Reporting Person (See Instructions)

OO

SCHEDULE 13D

CUSIP Number(s): 98937L105

1

Name of reporting person

Zebra Aggregator, LP

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

WC

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 3,245,404.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 3,245,404.00

11

Aggregate amount beneficially owned by each reporting person

3,245,404.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

4.9 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: Common Stock, par value $0.0001 per share
(b)	Name of Issuer: Zenas BioPharma, Inc.
(c)	Address of Issuer's Principal Executive Offices: 852 Winter Street, Suite 250, Waltham , MASSACHUSETTS , 02451.
Item 1 Comment: This Amendment No. 2 (this "Amendment No. 2" or this "Schedule 13D/A") amends and supplements the statement on Schedule 13D originally filed with the Securities and Exchange Commission (the "SEC") on September 23, 2024 and amended October 14, 2025 (as amended, the "Statement") by the Reporting Persons. Unless otherwise defined herein, capitalized terms used in this Amendment No. 2 shall have the meanings ascribed to them in the Statement. Unless amended or supplemented below, the information in the Statement remains unchanged.
Item 5.	Interest in Securities of the Issuer
(a)	Row 11 of each Reporting Person's cover page to this Schedule 13D/A sets forth the aggregate number of shares of common stock beneficially owned by such Reporting Person and is incorporated by reference. As of the date hereof, each Reporting Person beneficially owns 4.98% of the outstanding Common Stock of the Issuer. Such percentage is based upon 65,176,723 shares of common stock outstanding as of July 31, 2026, as reported in the Issuer's Quarterly Report on Form 10-Q filed with the SEC on August 13, 2026. Due to field limitations of the EDGAR filing system, the percentage listed in Row 13 of each of the cover pages has been rounded down to 4.9%. Zebra LP directly holds 3,245,404 shares of common stock. Enavate GP is the general partner of Zebra LP and shares voting and investment authority over the shares held by Zebra LP.
(b)	Rows 7 through 10 of each Reporting Person's cover page to this Schedule 13D/A set forth the number of shares of common stock as to which such Reporting Person has the sole or shared power to vote or direct the vote and sole or shared power to dispose or to direct the disposition and are incorporated by reference.
(c)	Except as set forth below, none of the Reporting Persons has effected any transactions with respect to the securities of the Issuer during the past sixty days. Weighted Low High Reporting No. Average Price Price Transaction Person Date Shares Price ($) ($) ($) Open Market Sale Zebra LP 08/19/2026 673,755 31.44 31.05 32.00
(d)	No other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of the common stock.
(e)	The Reporting Persons ceased to be the beneficial owners of more than five percent of the common stock on August 19, 2026.
Item 7.	Material to be Filed as Exhibits.
	Exhibit 99.1 Joint Filing Agreement (incorporated by reference to Exhibit A to the Reporting Persons' Schedule 13D filed with the SEC on September 23, 2024).

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Enavate Sciences GP, LLC

Signature:	/s/ James P. Boylan
Name/Title:	By James P. Boylan, Manager
Date:	08/19/2026

Zebra Aggregator, LP

Signature:	/s/ James P. Boylan
Name/Title:	By: Enavate Sciences GP, LLC, its General Partner, By James P. Boylan, Manager
Date:	08/19/2026