AKTS insider ownership: who sold, why, and what they still hold

What stands out

Todd Foley bought 233K shares for $4.2M, first on Jan 12, 2026. These are the first purchases by current officers or directors in the filings on record.Purchase, Jan 12, 2026

Two officers sold $2.8M with no disclosed plan: Akos Czibere ($1.4M) and Shulamit Ron-Bigger ($1.4M). The filings don't state a reason.Akos Czibere: largest such sale, Jul 8, 2026 · Shulamit Ron-Bigger: largest such sale, Jul 8, 2026

A share of stake is shown for 0 of the 3 officers and directors who sold. 12 are left out

Left out: Paul Feldman, Matthew Roden, Mary Thistle, Michael Sherman, Akos Czibere, Todd Foley, Shulamit Ron-Bigger, Lloyd Segal, Ken Herrmann, Helen Kim, Kyle Kuvalanka and Glenn Gormley (share of stake is being verified).

Disclosed company stock is not an insider's whole wealth.

Who sold, and how much of their stake

Officers and directors, past 12 months. Their share of stake is being verified and is not shown yet; amounts and trading plans are below.

Akos Czibere

Chief Medical Officer

Not confirmed

Share of stake not shown: share of stake is being verified. Why

$1.6M16% planned 84% no plan disclosed

Shulamit Ron-Bigger

Chief Operating Officer

Not confirmed

Share of stake not shown: share of stake is being verified. Why

$1.4MNo plan disclosed

Ken Herrmann

Director

Not confirmed

Share of stake not shown: share of stake is being verified. Why

$197KNo plan disclosed

Amounts, filings and trading plans for each seller

Selling by month

Officers and directors, Oct 2025 to Oct 2026. Each sale is counted once: under a disclosed plan, else to cover taxes, else no plan disclosed.

Disclosed planNo plan disclosedOne dollar scale for every month; the tallest bar is labeled

Recent activity

Past 30 days, Sep 14, 2026 to Oct 13, 2026

Sep 23, 2026Akos Czibere sold 13K shares ($259K) under a disclosed trading plan. 13K shares came in from vesting or option exercises the same day, so the holding rose by 0 net.

Who	Shares	Price	% of total stake	Total stake after	Trade date	Filed
Akos Czibere Chief Medical Officer	12,500	$20.69	n/a	n/a	Sep 23, 2026	Sep 24, 2026

"% of total stake" is the shares in an event against all the vested shares the person held that day, across every share class and holding entity, after that day's vesting. "n/a" means the person's holdings are not confirmed, or the row is a purchase. "Holdings record incomplete" means more shares were sold than the filings show the person held that day, so a percentage would be wrong.

Outside holders, reported separately

ELI LILLY & Co, MPM BIOVENTURES 2018, L.P. and Ansbert Gadicke and 3 more reported no open-market sales in the past 12 months. Large shareholders and the funds or companies that board members represent are not part of management, so they are left out of the figures above.

Details

Common questions

Is the Aktis Oncology, Inc. CEO selling stock?

No. Matthew Roden reported no open-market sales in the past 12 months.

Why are Aktis Oncology, Inc. insiders selling?

Filings rarely give a reason, and we don't guess at one. What they show is how the sales were made: 8% of sales by value ran under 10b5-1 trading plans disclosed in the filings and 92% had no disclosed plan. A trading plan schedules sales in advance.

Are any Aktis Oncology, Inc. insiders buying?

Yes. 1 officer or director reported 1 purchase in the past 12 months (Form 4 code P; rows the filings describe as reinvested dividends, plan purchases, private deals or moves into the person's own trust are not counted).

The evidence

Who sold3 officers and directors: amount, % of holdings, trading plan

Who sold	Amount	% of holdings	Trading plan
Akos Czibere Chief Medical Officer	$1.6M 63K shares	Not confirmed share of stake is being verified. Why	16% under a disclosed plan 84% no plan disclosed
Shulamit Ron-Bigger Chief Operating Officer	$1.4M 50K shares	Not confirmed share of stake is being verified. Why	No plan disclosed
Ken Herrmann Director	$197K 7.9K shares	Not confirmed share of stake is being verified. Why	No plan disclosed

Board members representing outside shareholders, reported separately: Helen Kim. Details

Outside holder, reported separately: ELI LILLY & Co (a 10% owner, not part of management). No open-market sales reported in the period. Latest filing

Outside holder, reported separately: MPM BIOVENTURES 2018, L.P. (a 10% owner, not part of management). No open-market sales reported in the period. Latest filing

Outside holder, reported separately: Ansbert Gadicke (a 10% owner, not part of management). No open-market sales reported in the period. Latest filing

Outside holder, reported separately: Vida Ventures II, LLC (a 10% owner, not part of management). No open-market sales reported in the period. Latest filing

Outside holder, reported separately: EcoR1 Capital, LLC (an outside shareholder, not part of management). No open-market sales reported in the period. Latest filing

The full ownership picture0 of 12 officers and directors confirmed

Vested shares across all share classes, held directly and through trusts, LLCs and family members, as reported on SEC Forms 3, 4 and 5. Unvested awards and options are never counted as owned shares.

Insider

Held Oct 13, 2025

Sold

Held Oct 13, 2026

Still held

Paul Feldman

Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Paul Feldman are complete.

Chief Scientific Officer

n/a

Vesting, gifts, unvested awards and holding lines for Paul Feldman

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Paul Feldman are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options held	Strike price	Expires	Intrinsic value (estimate)
65,713	$1.91	Apr 14, 2031	$1.3M
119,248	$3.66	Nov 15, 2032	$2.1M
90,684	$9.33	Oct 10, 2034	$1.1M
131,246	$18.00	Jan 7, 2036	$398K

Estimate: options held × ($21.03 − strike price), using the most recent insider trade price on Form 4 (Sep 23, 2026), not a market close.

Matthew Roden

President and CEO, Director

n/a

Vesting, gifts, unvested awards and holding lines for Matthew Roden

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Matthew Roden are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options held	Strike price	Expires	Intrinsic value (estimate)
578,277	$1.91	Apr 14, 2031	$11.1M
558,095	$3.66	Nov 15, 2032	$9.7M
618,757	$9.33	Oct 10, 2034	$7.2M
394,280	$18.00	Jan 7, 2036	$1.2M

Estimate: options held × ($21.03 − strike price), using the most recent insider trade price on Form 4 (Sep 23, 2026), not a market close.

Mary Thistle

Director

n/a

Vesting, gifts, unvested awards and holding lines for Mary Thistle

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Mary Thistle are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options held	Strike price	Expires	Intrinsic value (estimate)
74,913	$10.66	Jan 14, 2035	$777K
18,933	$18.00	Jan 7, 2036	$57K

Estimate: options held × ($21.03 − strike price), using the most recent insider trade price on Form 4 (Sep 23, 2026), not a market close.

Michael Sherman

Director

n/a

Vesting, gifts, unvested awards and holding lines for Michael Sherman

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Michael Sherman are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options held	Strike price	Expires	Intrinsic value (estimate)
74,913	$9.14	Oct 8, 2035	$891K
18,933	$18.00	Jan 7, 2036	$57K

Estimate: options held × ($21.03 − strike price), using the most recent insider trade price on Form 4 (Sep 23, 2026), not a market close.

Akos Czibere

Chief Medical Officer

n/a

−63K

n/a

Vesting, gifts, unvested awards and holding lines for Akos Czibere

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Akos Czibere are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options held	Strike price	Expires	Intrinsic value (estimate)
208,718	$4.95	Jun 30, 2034	$3.4M
98,570	$9.33	Oct 10, 2034	$1.2M
19,714	$11.46	Dec 11, 2035	$189K
131,426	$18.00	Jan 7, 2036	$398K

Estimate: options held × ($21.03 − strike price), using the most recent insider trade price on Form 4 (Sep 23, 2026), not a market close.

Todd Foley

Director

n/a

Vesting, gifts, unvested awards and holding lines for Todd Foley

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Todd Foley are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options held	Strike price	Expires	Intrinsic value (estimate)
37,866	$18.00	Jan 7, 2036	$115K

Estimate: options held × ($21.03 − strike price), using the most recent insider trade price on Form 4 (Sep 23, 2026), not a market close.

Shulamit Ron-Bigger

Chief Operating Officer

n/a

−50K

n/a

Vesting, gifts, unvested awards and holding lines for Shulamit Ron-Bigger

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Shulamit Ron-Bigger are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options held	Strike price	Expires	Intrinsic value (estimate)
217,888	$3.66	Oct 30, 2032	$3.8M
18,697	$4.95	Jun 30, 2034	$301K
118,284	$9.33	Oct 10, 2034	$1.4M
131,426	$18.00	Jan 7, 2036	$398K

Estimate: options held × ($21.03 − strike price), using the most recent insider trade price on Form 4 (Sep 23, 2026), not a market close.

Lloyd Segal

Director

n/a

Vesting, gifts, unvested awards and holding lines for Lloyd Segal

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Lloyd Segal are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options held	Strike price	Expires	Intrinsic value (estimate)
32,856	$1.45	Feb 21, 2031	$643K
31,542	$3.66	Nov 15, 2032	$548K
6,571	$4.95	Jun 30, 2034	$106K
10,514	$10.66	Dec 9, 2034	$109K
18,933	$18.00	Jan 7, 2036	$57K

Estimate: options held × ($21.03 − strike price), using the most recent insider trade price on Form 4 (Sep 23, 2026), not a market close.

Ken Herrmann

Director

n/a

−7.9K

n/a

Vesting, gifts, unvested awards and holding lines for Ken Herrmann

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Ken Herrmann are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options held	Strike price	Expires	Intrinsic value (estimate)
18,364	$1.91	Apr 14, 2031	$351K
26,285	$3.66	Nov 15, 2032	$457K
64,399	$4.95	Jun 30, 2034	$1.0M
10,514	$10.66	Dec 9, 2034	$109K
18,933	$18.00	Jan 7, 2036	$57K

Estimate: options held × ($21.03 − strike price), using the most recent insider trade price on Form 4 (Sep 23, 2026), not a market close.

Helen Kim

Director

n/a

Vesting, gifts, unvested awards and holding lines for Helen Kim

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Helen Kim are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options held	Strike price	Expires	Intrinsic value (estimate)
37,866	$18.00	Jan 7, 2036	$115K

Estimate: options held × ($21.03 − strike price), using the most recent insider trade price on Form 4 (Sep 23, 2026), not a market close.

Kyle Kuvalanka

Chief Financial Officer

n/a

Vesting, gifts, unvested awards and holding lines for Kyle Kuvalanka

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Kyle Kuvalanka are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options held	Strike price	Expires	Intrinsic value (estimate)
370,423	$11.46	Dec 11, 2035	$3.5M
131,426	$18.00	Jan 7, 2036	$398K

Estimate: options held × ($21.03 − strike price), using the most recent insider trade price on Form 4 (Sep 23, 2026), not a market close.

Glenn Gormley

Director

n/a

Vesting, gifts, unvested awards and holding lines for Glenn Gormley

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Glenn Gormley are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options held	Strike price	Expires	Intrinsic value (estimate)
37,866	$18.09	Apr 15, 2036	$111K

Estimate: options held × ($21.03 − strike price), using the most recent insider trade price on Form 4 (Sep 23, 2026), not a market close.

Holdings and share of stake for Aktis Oncology, Inc. are being verified, so no balances, unit counts or percentages are shown. Sales, proceeds, plan and tax status, titles and dates come straight from individual filings.

What explains the selling$3.2M of sales by plan status, purpose, seller and month

Officer and director open-market sales: $3.2M across 120,421 shares. Plan status and stated purpose are separate questions, and a sale can have both.

By plan status

Disclosed plan · $259K · 8%

92%

The lighter segment is sales with no plan disclosed in the filing ($3.0M), including tax-related sales outside a plan.

No plan disclosed · $3.0M

Sales with no 10b5-1 plan and no tax reference in the filing. $1.4M of it is Akos Czibere. No plan disclosed is a statement about the filing, not about why the sale happened. Largest such sale: Akos Czibere, Jul 8, 2026

Purchases · 1 buyer (1 trade)

1 officer or director bought shares in this period, in 1 trade(Form 4 code P, leaving out rows the filings describe as reinvested dividends, plan purchases, private deals or moves into the person's own trust). Across all their filings on record there is 1 purchase trade.

Seller	Shares sold	Proceeds	Under a disclosed plan	Share of total	Sales dates
Akos Czibere Chief Medical Officer	63K	$1.6M	16%	51%	Jul 8, 2026 to Sep 23, 2026
Shulamit Ron-Bigger Chief Operating Officer	50K	$1.4M	0%	43%	Jul 8, 2026 to Jul 8, 2026
Ken Herrmann Director	7.9K	$197K	0%	6%	Jul 17, 2026 to Jul 20, 2026

Sales by month

Month	Sale proceeds	Disclosed plan	To cover taxes	No plan disclosed
Oct 2025	$0	$0	$0	$0
Nov 2025	$0	$0	$0	$0
Dec 2025	$0	$0	$0	$0
Jan 2026	$0	$0	$0	$0
Feb 2026	$0	$0	$0	$0
Mar 2026	$0	$0	$0	$0
Apr 2026	$0	$0	$0	$0
May 2026	$0	$0	$0	$0
Jun 2026	$0	$0	$0	$0
Jul 2026	$3.0M	$0	$0	$3.0M
Aug 2026	$0	$0	$0	$0
Sep 2026	$259K	$259K	$0	$0
Oct 2026	$0	$0	$0	$0

Board members representing outside shareholders (1)Listed and sourced; not part of the management totals or the answer line

Directors whose reported holdings sit mostly in an investment fund or a corporate shareholder they represent, not in their own name, with beneficial ownership disclaimed except for their own financial interest. Listed and sourced here; not part of the management totals or the answer line. Shares a fund hands to its own investors are distributions, not sales.

Board member	Held Oct 13, 2025	Sold	Held Oct 13, 2026	Still held
Helen Kim ! Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Helen Kim are complete. Director	n/a	0	n/a	n/a
Vesting, gifts, unvested awards and holding lines for Helen Kim Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Helen Kim are complete; balances and unit counts will be added when the check is finished. 0gifted (net of own trusts)

Known gaps and uncertainty12 officers and directors not confirmed

Holdings and share of stake are being verified. Balances, unit counts and every share-of-stake figure for Aktis Oncology, Inc. are held back until that check is finished. Sales, proceeds, plan and tax status, titles and dates come straight from individual filings and are complete.

External context: we only cite outside events when a documented connection exists. None is shown for this period.

Sources and methodology30 filings on record, 30 filed in the 12-month period, and how we read them

All 30 Forms 3, 4 and 5 on record for Aktis Oncology, Inc. (SEC CIK 2035832), filed from Jan 8, 2026 to Sep 24, 2026; 30 of them were filed in the 12 months this page covers, retrieved from SEC EDGAR on Oct 13, 2026. Prices are the ones reported in each filing, often weighted averages.

Holdings. Each holding line (a share class plus an owner, such as a trust or LLC) carries its last reported balance forward. Entities first reported during the period start at zero, so transfers between an insider's own trusts don't count as selling. Lines not reported for three years or more are listed separately and left out of totals.

Sales. A sale counts as under a 10b5-1 plan if its footnote cites one or the filing's Rule 10b5-1 box is checked, and as tax-related if its footnote cites tax obligations or sell-to-cover. Shares withheld by the company for taxes are listed separately. Sales with neither attribute are labeled "no plan disclosed".

Full methodology

Spotted something wrong on this page? Report an error. We check every report against the SEC filing and list what we fix in the corrections log.

Aktis Oncology, Inc. insiders sold $3.2M in the past 12 months. How much of their stake is that?

What stands out

Who sold, and how much of their stake

Selling by month

Recent activity

Outside holders, reported separately

Common questions

Is the Aktis Oncology, Inc. CEO selling stock?

Why are Aktis Oncology, Inc. insiders selling?

Are any Aktis Oncology, Inc. insiders buying?

The evidence

No plan disclosed · $3.0M

Purchases · 1 buyer (1 trade)

Sales by month