Company · Ownership research

Zenas BioPharma, Inc. ZBIO

CIK 0001953926

Form 4 transactions dated Nov 1, 2023 to Nov 9, 2026, as reported to the SEC.

Insider trading Initial holdings Institutional holders

Insider filings on file run through Sep 2, 2026.

Some filings are submitted jointly by several insiders. The SEC form does not apportion the reported figures between them, so results include every joint filer.

Insider purchases & sales

Purchased: $113.10M
Sold: $0.00

Nov 1, 2023 – Sep 2, 2026
Available records · partial months are marked ·

202610 of 15 preview events

Date	Insider	Activity	Trade value (USD)	% of prior holding
May 18, 2026	MOULDER LEON O JR Chief Executive Officer · Director	Purchase	$1.01M 60,000 shares bought	162.48% added Indirect holding	▾
Apr 29, 2026	MOULDER LEON O JR Chief Executive Officer · Director	Purchase	$616.70K 35,000 shares bought	2.00% added Indirect holding	▾
Apr 28, 2026	MOULDER LEON O JR Chief Executive Officer · Director	Purchase	$450.50K 25,000 shares bought	1.45% added Indirect holding	▾
Mar 31, 2026	Lu Hongbo Director	Purchase	$70.20K 3,768 shares bought	0.89% added Indirect holding	▾
Mar 31, 2026	Harwin Peter Evan · Fairmount Healthcare Fund II L.P. · Fairmount Funds Management LLC · Kiselak Tomas Director	Purchase	$3.00M 150,000 shares bought	Unavailable Indirect holding	▾
Mar 31, 2026	MOULDER LEON O JR Chief Executive Officer · Director	Purchase	$656.54K 34,000 shares bought	2.01% added Indirect holding	▾
Mar 31, 2026	Lu Hongbo Director	Purchase	$1.50M 75,000 shares bought	21.55% added Indirect holding	▾
Mar 30, 2026	MOULDER LEON O JR Chief Executive Officer · Director	Purchase	$364.60K 20,000 shares bought	1.20% added Indirect holding	▾
Feb 13, 2026	Allen Patricia L Director	Purchase	$109.66K 4,160 shares bought	26.50% added Direct holding	▾
Feb 12, 2026	Allen Patricia L Director	Purchase	$390.09K 15,700 shares bought	New holding Direct holding	▾

Showing 15 / 15 record groups in 2026. The complete set is available through the API.

Zenas BioPharma, Inc. · ZBIO

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The initial HTML of this page carries its exact data as script#research-data (JSON): values, units, scope, preview limits and SEC sources. Read it directly, no script or API key needed; script#research-access says what needs an account. For the year shown, this page lists 15 of 15 purchase / sale groups and 11 of 11 other groups; the totals and the monthly series cover the whole window.

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{"action":"list","ticker":"ZBIO","transaction_code":["P","S"],"transaction_form_type":"4","page_size":20}

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Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.

Non-cancelled, non-derivative purchase (P) and sale (S) rows dated inside the public window, as reported. Share totals are on today's split-adjusted basis. Includes open-market and private transactions. Data after the latest filing is not asserted complete and is not zero-filled. A grouped event shares filing, transaction date, security, code, direction, ownership bucket and source. Derivative groups also match underlying security, exercise price, exercise/expiration dates and footnote references. Reported rows are retained; P/S price lots can be grouped. Post-transaction balances are never summed.