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

What stands out

Three insiders sold $19.1M with no disclosed plan: Chad Robins ($14.9M), Peter Neupert ($3.1M) and Robert Hershberg ($1.1M). The filings don't state a reason.Chad Robins: largest such sale, Aug 17, 2026 · Peter Neupert: largest such sale, Aug 17, 2026 · Robert Hershberg: largest such sale, Aug 18, 2026

A share of stake is shown for 0 of the 11 officers and directors who sold. 11 are left out

Left out: Chad Robins, Harlan Robins, Julie Rubinstein, Sharon Benzeno, Susan Bobulsky, Francis Lo, Kyle Piskel, Peter Neupert, Katey Owen, Robert Hershberg and Michelle Griffin (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.

Chad Robins

CEO and Chairman, Director

Not confirmed

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

$39.8M47% planned, 16% to cover taxes 37% no plan disclosed

Harlan Robins

Chief Scientific Officer

Not confirmed

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

$29.6M79% planned, 21% to cover taxes

Julie Rubinstein

President and COO

Not confirmed

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

$15.3MDisclosed plan

Sharon Benzeno

Chief Commercial Ofc Imm Med

Not confirmed

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

$14.7M94% planned, 6% to cover taxes

Francis Lo

Chief People Officer

Not confirmed

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

$13.9M96% planned, 4% to cover taxes

All 11 sellers

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 planTo cover taxesNo plan disclosedOne dollar scale for every month; the tallest bar is labeled

Recent activity

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

Oct 8, 2026Julie Rubinstein sold 12K shares ($305K) under a disclosed trading plan. 12K 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
Julie Rubinstein President and COO	11,881	$25.66	n/a	n/a	Oct 8, 2026	Oct 8, 2026

Oct 7, 2026Julie Rubinstein sold 12K shares ($314K) under a disclosed trading plan. 12K 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
Julie Rubinstein President and COO	11,881	$26.40	n/a	n/a	Oct 7, 2026	Oct 8, 2026

Oct 6, 20262 executives sold 18K shares ($523K) under a disclosed trading plan. 12K shares came in from vesting or option exercises the same day, so their combined holdings fell by 6.4K net.

Who	Shares	Price	% of total stake	Total stake after	Trade date	Filed
Julie Rubinstein President and COO	11,881	$27.75	n/a	n/a	Oct 6, 2026	Oct 8, 2026
Susan Bobulsky Chief Commercial Officer, MRD	6,444	$30.00	n/a	n/a	Oct 6, 2026	Oct 8, 2026

Oct 5, 2026Julie Rubinstein sold 12K shares ($347K) under a disclosed trading plan. 12K 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
Julie Rubinstein President and COO	11,881	$29.19	n/a	n/a	Oct 5, 2026	Oct 5, 2026

Oct 2, 2026Julie Rubinstein sold 12K shares ($334K) under a disclosed trading plan. 12K 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
Julie Rubinstein President and COO	11,881	$28.13	n/a	n/a	Oct 2, 2026	Oct 5, 2026

Show all 8 events

Oct 1, 20262 executives sold 39K shares ($1.1M) under a disclosed trading plan. 39K shares came in from vesting or option exercises the same day, so their combined holdings rose by 0 net.

Who	Shares	Price	% of total stake	Total stake after	Trade date	Filed
Francis Lo Chief People Officer	26,792	$28.28	n/a	n/a	Oct 1, 2026	Oct 5, 2026
Julie Rubinstein President and COO	11,881	$28.05	n/a	n/a	Oct 1, 2026	Oct 5, 2026

Sep 16, 2026Francis Lo sold 115K shares ($3.2M) under a disclosed trading plan. 106K shares came in from vesting or option exercises the same day, so the holding fell by 9.8K net.

Who	Shares	Price	% of total stake	Total stake after	Trade date	Filed
Francis Lo Chief People Officer	115,406	$28.06	n/a	n/a	Sep 16, 2026	Sep 18, 2026

Sep 15, 2026Susan Bobulsky sold 1.2K shares ($32K) under a disclosed trading plan.

Who	Shares	Price	% of total stake	Total stake after	Trade date	Filed
Susan Bobulsky Chief Commercial Officer, MRD	1,195	$27.00	n/a	n/a	Sep 15, 2026	Sep 17, 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.

Common questions

Is the Adaptive Biotechnologies Corp CEO selling stock?

Yes. Chad Robins sold 2.22M shares ($39.8M) in the past 12 months, 47% of it under a trading plan disclosed in the filings.

Why are Adaptive Biotechnologies Corp insiders selling?

Filings rarely give a reason, and we don't guess at one. What they show is how the sales were made: 73% of sales by value ran under 10b5-1 trading plans disclosed in the filings, 12% were to cover taxes and 16% had no disclosed plan. A trading plan schedules sales in advance.

Are any Adaptive Biotechnologies Corp insiders buying?

No. Officers and directors reported no purchases in the past 12 months.

The evidence

Who sold11 officers and directors: amount, % of holdings, trading plan

Who sold	Amount	% of holdings	Trading plan
Chad Robins CEO and Chairman, Director	$39.8M 2.22M shares	Not confirmed share of stake is being verified. Why	47% under a disclosed plan, 16% to cover taxes 37% no plan disclosed
Harlan Robins Chief Scientific Officer	$29.6M 1.59M shares	Not confirmed share of stake is being verified. Why	79% under a disclosed plan, 21% to cover taxes
Julie Rubinstein President and COO	$15.3M 1.02M shares	Not confirmed share of stake is being verified. Why	Disclosed plan
Sharon Benzeno Chief Commercial Ofc Imm Med	$14.7M 848K shares	Not confirmed share of stake is being verified. Why	94% under a disclosed plan, 6% to cover taxes
Francis Lo Chief People Officer	$13.9M 676K shares	Not confirmed share of stake is being verified. Why	96% under a disclosed plan, 4% to cover taxes
Kyle Piskel Chief Financial Officer	$3.6M 191K shares	Not confirmed share of stake is being verified. Why	92% under a disclosed plan, 8% to cover taxes
Peter Neupert Director	$3.1M 125K shares	Not confirmed share of stake is being verified. Why	No plan disclosed
Michelle Griffin Director	$2.0M 116K shares	Not confirmed share of stake is being verified. Why	89% under a disclosed plan 11% no plan disclosed
Susan Bobulsky Chief Commercial Officer, MRD	$1.4M 80K shares	Not confirmed share of stake is being verified. Why	61% under a disclosed plan, 39% to cover taxes
Robert Hershberg Director	$1.1M 54K shares	Not confirmed share of stake is being verified. Why	No plan disclosed
Katey Owen Director	$250K 9.6K shares	Not confirmed share of stake is being verified. Why	No plan disclosed

The full ownership picture0 of 11 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

Chad Robins

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 Chad Robins are complete.

CEO and Chairman, Director

n/a

−2.22M

n/a

Vesting, gifts, unvested awards and holding lines for Chad Robins

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

0gifted (net of own trusts)

Some sales match sales reported by Harlan Robins exactly (date, shares and price). Possibly the same shares reported by both; the filings don't confirm it.

Harlan Robins

Chief Scientific Officer

n/a

−1.59M

n/a

Vesting, gifts, unvested awards and holding lines for Harlan Robins

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

0gifted (net of own trusts)

Some sales match sales reported by Chad Robins exactly (date, shares and price). Possibly the same shares reported by both; the filings don't confirm it.

Julie Rubinstein

President and COO

n/a

−1.02M

n/a

Vesting, gifts, unvested awards and holding lines for Julie Rubinstein

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Julie Rubinstein 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)
308,491	$12.14	Mar 4, 2032	$4.2M
45,731	$8.46	Mar 6, 2033	$787K

Estimate: options held × ($25.66 − strike price), using the most recent insider trade price on Form 4 (Oct 8, 2026), not a market close.

Sharon Benzeno

Chief Commercial Ofc Imm Med

n/a

−848K

n/a

Vesting, gifts, unvested awards and holding lines for Sharon Benzeno

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Sharon Benzeno 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)
37,416	$8.46	Mar 6, 2033	$644K
87,303	$3.99	Mar 4, 2034	$1.9M
113,457	$8.12	Mar 4, 2035	$2.0M

Estimate: options held × ($25.66 − strike price), using the most recent insider trade price on Form 4 (Oct 8, 2026), not a market close.

Susan Bobulsky

Chief Commercial Officer, MRD

n/a

−80K

n/a

Vesting, gifts, unvested awards and holding lines for Susan Bobulsky

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Susan Bobulsky 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)
20,000	$6.27	Apr 25, 2027	$388K
28,750	$6.55	Apr 24, 2028	$549K
13,474	$28.32	Feb 27, 2030	$0
20,000	$39.50	Aug 13, 2030	$0
22,894	$43.68	Mar 4, 2031	$0
102,965	$12.14	Mar 4, 2032	$1.4M
88,689	$8.46	Mar 6, 2033	$1.5M
199,549	$3.99	Mar 4, 2034	$4.3M
180,029	$8.12	Mar 4, 2035	$3.2M

Estimate: options held × ($25.66 − strike price), using the most recent insider trade price on Form 4 (Oct 8, 2026), not a market close.

Francis Lo

Chief People Officer

n/a

−676K

n/a

Vesting, gifts, unvested awards and holding lines for Francis Lo

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Francis Lo 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)
79,155	$12.14	Mar 4, 2032	$1.1M
16,075	$8.46	Mar 6, 2033	$276K
56,259	$3.99	Mar 4, 2034	$1.2M
93,765	$8.12	Mar 4, 2035	$1.6M

Estimate: options held × ($25.66 − strike price), using the most recent insider trade price on Form 4 (Oct 8, 2026), not a market close.

Kyle Piskel

Chief Financial Officer

n/a

−191K

n/a

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

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Kyle Piskel 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)
2,146	$12.14	Mar 4, 2032	$29K

Estimate: options held × ($25.66 − strike price), using the most recent insider trade price on Form 4 (Oct 8, 2026), not a market close.

Peter Neupert

Director

n/a

−125K

n/a

Vesting, gifts, unvested awards and holding lines for Peter Neupert

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Peter Neupert 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)
48,044	$3.99	Mar 4, 2034	$1.0M
23,726	$8.12	Mar 4, 2035	$416K

Estimate: options held × ($25.66 − strike price), using the most recent insider trade price on Form 4 (Oct 8, 2026), not a market close.

Katey Owen

Director

n/a

−9.6K

n/a

Vesting, gifts, unvested awards and holding lines for Katey Owen

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

−13Kgifted (net of own trusts)

Stock options (not counted as shares):

Options held	Strike price	Expires	Intrinsic value (estimate)
48,044	$3.99	Mar 4, 2034	$1.0M
23,726	$8.12	Mar 4, 2035	$416K

Estimate: options held × ($25.66 − strike price), using the most recent insider trade price on Form 4 (Oct 8, 2026), not a market close.

Robert Hershberg

Director

n/a

−54K

n/a

Vesting, gifts, unvested awards and holding lines for Robert Hershberg

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Robert Hershberg 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)
48,044	$3.99	Mar 4, 2034	$1.0M
23,726	$8.12	Mar 4, 2035	$416K

Estimate: options held × ($25.66 − strike price), using the most recent insider trade price on Form 4 (Oct 8, 2026), not a market close.

Michelle Griffin

Director

n/a

−116K

n/a

Vesting, gifts, unvested awards and holding lines for Michelle Griffin

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Michelle Griffin 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)
23,726	$8.12	Mar 4, 2035	$416K

Estimate: options held × ($25.66 − strike price), using the most recent insider trade price on Form 4 (Oct 8, 2026), not a market close.

Holdings and share of stake for Adaptive Biotechnologies Corp 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$125M of sales by plan status, purpose, seller and month

Officer and director open-market sales: $125M across 6,923,933 shares. Plan status and stated purpose are separate questions, and a sale can have both.

By plan status

Disclosed plan · $90.6M · 73%

27%

The lighter segment is sales with no plan disclosed in the filing ($34.2M), including tax-related sales outside a plan.

No plan disclosed · $19.6M

Sales with no 10b5-1 plan and no tax reference in the filing. $14.9M of it is Chad Robins. No plan disclosed is a statement about the filing, not about why the sale happened. Largest such sale: Chad Robins, Aug 17, 2026

Taxes

$16.2M of sales (13.0%) cite tax obligations in their footnotes, $1.6M of them also under a plan. Example: Kyle Piskel, May 18, 2026

Seller	Shares sold	Proceeds	Under a disclosed plan	Share of total	Sales dates
Chad Robins CEO and Chairman, Director	2.22M	$39.8M	47%	32%	Nov 10, 2025 to Aug 18, 2026
Harlan Robins Chief Scientific Officer	1.59M	$29.6M	79%	24%	Nov 10, 2025 to Jul 21, 2026
Julie Rubinstein President and COO	1.02M	$15.3M	100%	12%	Mar 3, 2026 to Oct 8, 2026
Sharon Benzeno Chief Commercial Ofc Imm Med	848K	$14.7M	94%	12%	Nov 20, 2025 to Jun 29, 2026
Francis Lo Chief People Officer	676K	$13.9M	96%	11%	Dec 15, 2025 to Oct 1, 2026
Kyle Piskel Chief Financial Officer	191K	$3.6M	92%	3%	Nov 17, 2025 to May 18, 2026
Peter Neupert Director	125K	$3.1M	0%	3%	Aug 17, 2026 to Aug 17, 2026
Michelle Griffin Director	116K	$2.0M	89%	2%	Mar 3, 2026 to Jun 25, 2026
Susan Bobulsky Chief Commercial Officer, MRD	80K	$1.4M	61%	1%	Mar 11, 2026 to Oct 6, 2026
Robert Hershberg Director	54K	$1.1M	0%	0.9%	Dec 10, 2025 to Aug 18, 2026
Katey Owen Director	9.6K	$250K	0%	0.2%	Aug 26, 2026 to Aug 26, 2026

Sales by month

Month	Sale proceeds	Disclosed plan	To cover taxes	No plan disclosed
Oct 2025	$0	$0	$0	$0
Nov 2025	$15.5M	$15.5M	$3K	$0
Dec 2025	$5.5M	$5.1M	$0	$367K
Jan 2026	$3.7M	$3.7M	$0	$0
Feb 2026	$6.1M	$6.1M	$0	$0
Mar 2026	$29.9M	$15.1M	$14.6M	$214K
Apr 2026	$7.5M	$7.5M	$0	$0
May 2026	$41K	$0	$41K	$0
Jun 2026	$7.5M	$7.5M	$0	$0
Jul 2026	$24.0M	$24.0M	$0	$0
Aug 2026	$19.1M	$75K	$0	$19.0M
Sep 2026	$3.3M	$3.3M	$0	$0
Oct 2026	$2.9M	$2.9M	$0	$0

Is this normal? Selling year by year5 earlier years to compare with

More than usual: about 6x the 5-year average. 11 insiders sold; the average is 11 a year.

12 months ending	Shares sold	Insiders who sold	Proceeds
Oct 13, 2026 Latest 12 months	6.92M	11	$125M
Oct 13, 2025 1 year earlier	1.42M	10	$11.2M
Oct 13, 2024 2 years earlier	209K	8	$747K
Oct 14, 2023 3 years earlier	403K	9	$3.3M
Oct 14, 2022 4 years earlier	153K	11	$2.8M
Oct 14, 2021 5 years earlier	3.28M	18	$171M

Open-market sales (Form 4 code S) by people who were officers or directors, in split-adjusted shares. Earlier years include people who have since left. A sale that an outside holder also reports (a family trust, a fund) is counted with outside holders in every year. Shares, not dollars, are compared, so a change in the stock price doesn't look like a change in selling. Years the filings don't fully cover are shown but left out of the average.

Known gaps and uncertainty11 officers and directors not confirmed

Holdings and share of stake are being verified. Balances, unit counts and every share-of-stake figure for Adaptive Biotechnologies Corp 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 methodology533 filings on record, 86 filed in the 12-month period, and how we read them

All 533 Forms 3, 4 and 5 on record for Adaptive Biotechnologies Corp (SEC CIK 1478320), filed from Jun 26, 2019 to Oct 8, 2026; 86 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

Former or inactive filers (18)No filing in 18 months; last reported balances, not in any total

Name	Last filed	Last reported balance
Michael Pellini	Mar 6, 2025	69,690 shares, last reported balance as of Mar 4, 2025
Stacy Taylor	Aug 23, 2024	139,365 shares, last reported balance as of Aug 22, 2024
Tycho Peterson	Mar 6, 2024	531,553 shares, last reported balance as of Mar 5, 2024
Nitin Sood	Aug 8, 2023	214,808 shares, last reported balance as of Aug 8, 2023
Mark Adams	Apr 12, 2023	175,361 shares, last reported balance as of Apr 11, 2023
Kevin Conroy	Mar 8, 2023	22,968 shares, last reported balance as of Mar 6, 2023
Leslie Trigg	Mar 8, 2023	25,907 shares, last reported balance as of Mar 6, 2023
Lance Baldo	Mar 10, 2022	17,171 shares, last reported balance as of Mar 8, 2022
Chad Cohen	Dec 23, 2021	21,604 shares, last reported balance as of Dec 22, 2021
Jyoti Palaniappan	Jul 19, 2021	9,158 shares, last reported balance as of Jul 19, 2021
Henning Thorsen	May 19, 2021	29,061 shares, last reported balance as of May 17, 2021
David Goel	Mar 10, 2021	12,310,594 shares, last reported balance as of Mar 10, 2021
Eric Dobmeier	Feb 17, 2021	1,504 shares, last reported balance as of Feb 14, 2021
Nancy Hill	Jan 21, 2021	11,200 shares, last reported balance as of Jan 19, 2021
VIKING GLOBAL INVESTORS LP	Dec 16, 2020	29,993,708 shares, last reported balance as of Dec 14, 2020
Charles Sang	Dec 11, 2020	No balance on record
Andris Zoltners	Feb 18, 2020	3,621,016 shares, last reported balance as of Jan 28, 2020
Sean Nolan	Jun 26, 2019	No balance on record

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.

Adaptive Biotechnologies Corp insiders sold $125M 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

Common questions

Is the Adaptive Biotechnologies Corp CEO selling stock?

Why are Adaptive Biotechnologies Corp insiders selling?

Are any Adaptive Biotechnologies Corp insiders buying?

The evidence

No plan disclosed · $19.6M

Taxes

Sales by month