Person · CIK 1498428

John Cox

CEO & President at Dyne Therapeutics

Earlier: Sigilon Therapeutics, Repligen, Bioverativ and Biogen

Source: Forms 3, 4, 5 and 144 on SEC EDGAR

Sold on Form 4$15.3M

Noticed on Form 144$582K

Bought on Form 4$2M

Companies5

Holdings now

As reported after the latest Form 3, 4 or 5 at each company.

How these figures work

Options and RSUs are from the latest filing that lists them; earlier grants may also be held. Holdings can be out of date when a person stops filing.

Company	Security	Held	Shares or units	As of
Dyne Therapeutics DYN	Common Stock	Directly	357,507	Sep 8, 2026 · Filing · EDGAR
Dyne Therapeutics DYN	Common Stock	By Trust #1	18,000	Sep 8, 2026 · Filing · EDGAR
Dyne Therapeutics DYN	Common Stock	By Trust #2	18,000	Sep 8, 2026 · Filing · EDGAR
Dyne Therapeutics DYN	Common Stock	By Trust #3	18,000	Sep 8, 2026 · Filing · EDGAR
Dyne Therapeutics DYN	Common Stock	By Trust #4	18,000	Sep 8, 2026 · Filing · EDGAR
Dyne Therapeutics DYN	Stock option (right to buy) exercise $16.00, expires Feb 11, 2036, into Common Stock	Directly	285,000	Feb 12, 2026 · Filing · EDGAR
Sigilon Therapeutics	Common Stock	See Footnote	4,444	Dec 8, 2020 · Filing · EDGAR
Repligen	Common Stock	Directly	923	Mar 24, 2020 · Filing · EDGAR
Biogen	Common Stock	Directly	39,045.24	Apr 1, 2016 · Filing · EDGAR

Sold and noticed by quarter

Sold (Form 4) Noticed (Form 144) Bought (Form 4)

Quarterly totals as a table

Quarter	Sold (Form 4)	Noticed (Form 144)	Bought (Form 4)
Q3 2026	$238K	$238K	—
Q2 2026	$110K	$110K	—
Q1 2026	$41K	$41K	—
Q4 2025	$55K	$55K	—
Q3 2025	$35K	$35K	$911K
Q2 2025	$54K	$54K	—
Q1 2025	$48K	$48K	—
Q3 2024	—	—	$1.1M
Q1 2020	$4.1M	Not machine-readable	—
Q1 2015	$5.4M	Not machine-readable	—
Q4 2011	$249K	Not machine-readable	—
Q2 2011	$3.9M	Not machine-readable	—
Q1 2011	$614K	Not machine-readable	—
Q4 2010	$532K	Not machine-readable	—

Form 144 notices went onto EDGAR as structured data on April 13, 2023. Earlier notices were filed on paper and cannot be read here, so those quarters show no noticed amount.

Planned sales (Form 144) and the sales that followed

Each Form 144 notice of a planned sale, grouped by broker and 10b5-1 plan, with the Form 4 sales we matched to it.

How we match

A Form 144 is a notice of a planned sale by an affiliate. SEC Tracker matches each notice to Form 4 sales by the same person at the same company within 90 days of the notice, up to the shares noticed. The match is our inference, not something either filing states.

Notice date	Noticed	Planned sale	Outcome	Links
Dyne Therapeutics DYN · Stifel Nicolaus & Company · No 10b5-1 plan stated · 9 notices
Sep 8, 2026	5,658 · ~$107K	Sep 8, 2026	Sold as noticed Sold 5,658 at $18.88 on Sep 8 · $107K Form 4	Filing · EDGAR
Aug 13, 2026	4,986 · ~$131K	Aug 13, 2026	Sold as noticed Sold 4,986 at $26.28 on Aug 13 · $131K Form 4	Filing · EDGAR
Jun 16, 2026	2,683 · ~$49K	Jun 16, 2026	Sold as noticed Sold 2,683 at $18.33 on Jun 16 · $49K Form 4	Filing · EDGAR
May 13, 2026	3,311 · ~$61K	May 13, 2026	Sold as noticed Sold 3,311 at $18.36 on May 13 · $61K Form 4	Filing · EDGAR
Mar 5, 2026	2,732 · ~$41K	Mar 5, 2026	Sold as noticed Sold 2,732 at $14.90 on Mar 5 · $41K Form 4	Filing · EDGAR
Dec 5, 2025	2,662 · ~$55K	Dec 5, 2025	Sold as noticed Sold 2,662 at $20.72 on Dec 5 · $55K Form 4	Filing · EDGAR
Sep 5, 2025	2,640 · ~$35K	Sep 5, 2025	Sold as noticed Sold 2,640 at $13.41 on Sep 5 · $35K Form 4	Filing · EDGAR
Jun 5, 2025	4,060 · ~$54K	Jun 5, 2025	Sold as noticed Sold 4,060 at $13.35 on Jun 5 · $54K Form 4	Filing · EDGAR
Mar 5, 2025	4,067 · ~$48K	Mar 5, 2025	Sold as noticed Sold 4,061 at $11.83 on Mar 5 · $48K Form 4	Filing · EDGAR
Sales without a matching Form 144 · 20 sales No matching Form 144 found. Not every sale needs one: small sales and sales by people who are not affiliates are exempt.
—	—	—	Notice not machine-readable Repligen: Sold 1,858 at $96.72 on Mar 24, 2020 · $180K	Filing · EDGAR
—	—	—	Notice not machine-readable Repligen: Sold 1,016 at $97.17 on Mar 18, 2020 · $99K	Filing · EDGAR
—	—	—	Notice not machine-readable Repligen: Sold 1,187 at $96.45 on Mar 18, 2020 · $114K	Filing · EDGAR
—	—	—	Notice not machine-readable Repligen: Sold 24,533 at $95.13 on Mar 18, 2020 · $2.3M	Filing · EDGAR
—	—	—	Notice not machine-readable Repligen: Sold 10,000 at $93.39 on Mar 4, 2020 · $934K	Filing · EDGAR
—	—	—	Notice not machine-readable Repligen: Sold 4,355 at $92.76 on Feb 24, 2020 · $404K	Filing · EDGAR
—	—	—	Notice not machine-readable Repligen: Sold 100 at $94.85 on Feb 24, 2020 · $9K	Filing · EDGAR
—	—	—	Notice not machine-readable Biogen: Sold 12,010 at $449.06 on Mar 25, 2015 · $5.4M (10b5-1 plan)	Filing · EDGAR
—	—	—	Notice not machine-readable Biogen: Sold 2,175 at $114.37 on Nov 1, 2011 · $249K (10b5-1 plan)	Filing · EDGAR
—	—	—	Notice not machine-readable Biogen: Sold 4,350 at $100.00 on Apr 21, 2011 · $435K (10b5-1 plan)	Filing · EDGAR
—	—	—	Notice not machine-readable Biogen: Sold 36,234 at $80.00 on Apr 13, 2011 · $2.9M (10b5-1 plan)	Filing · EDGAR
—	—	—	Notice not machine-readable Biogen: Sold 6,900 at $78.00 on Apr 11, 2011 · $538K (10b5-1 plan)	Filing · EDGAR
—	—	—	Notice not machine-readable Biogen: Sold 2,840 at $73.00 on Mar 31, 2011 · $207K (10b5-1 plan)	Filing · EDGAR
—	—	—	Notice not machine-readable Biogen: Sold 100 at $70.45 on Mar 2, 2011 · $7K	Filing · EDGAR
—	—	—	Notice not machine-readable Biogen: Sold 2,483 at $70.08 on Mar 2, 2011 · $174K	Filing · EDGAR
—	—	—	Notice not machine-readable Biogen: Sold 1,458 at $70.11 on Mar 2, 2011 · $102K	Filing · EDGAR
—	—	—	Notice not machine-readable Biogen: Sold 1,843 at $67.08 on Feb 17, 2011 · $124K (10b5-1 plan)	Filing · EDGAR
—	—	—	Notice not machine-readable Biogen: Sold 773 at $62.87 on Nov 9, 2010 · $49K (10b5-1 plan)	Filing · EDGAR
—	—	—	Notice not machine-readable Biogen: Sold 765 at $63.04 on Nov 2, 2010 · $48K (10b5-1 plan)	Filing · EDGAR
—	—	—	Notice not machine-readable Biogen: Sold 6,900 at $63.00 on Oct 28, 2010 · $435K (10b5-1 plan)	Filing · EDGAR

Every transaction, by company

Each Form 3, 4 and 5 transaction in plain words, newest first.

How these figures work

Values are shares times the price each filing states; grants, exercises and gifts usually state no price. Held after is what the filing reports was held once the transaction was done, directly or through the named holder.

Dyne Therapeutics DYN CEO & President · filings 2024 to 2026 · sold $581K · bought $2M · $582K noticed on Form 144

Date	Transaction	Shares	Price	Value	Held after	Source
Sep 8, 2026	Sale under a 10b5-1 plan	−5,658	$18.88	$107K	357,507 direct	Filing · EDGAR
Aug 13, 2026	Sale under a 10b5-1 plan	−4,986	$26.28	$131K	363,165 direct	Filing · EDGAR
Jun 16, 2026	Sale under a 10b5-1 plan	−2,683	$18.33	$49K	368,151 direct	Filing · EDGAR
May 13, 2026	Sale under a 10b5-1 plan	−3,311	$18.36	$61K	370,834 direct	Filing · EDGAR
Mar 5, 2026	Sale under a 10b5-1 plan	−2,732	$14.90	$41K	374,145 direct	Filing · EDGAR
Feb 12, 2026	Grant or award from the company	+180,000			376,877 direct	Filing · EDGAR
Feb 12, 2026	Grant or award from the company Stock option (right to buy)	+285,000			285,000 direct	Filing · EDGAR
Dec 5, 2025	Sale under a 10b5-1 plan	−2,662	$20.72	$55K	196,877 direct	Filing · EDGAR
Sep 5, 2025	Sale under a 10b5-1 plan	−2,640	$13.41	$35K	199,539 direct	Filing · EDGAR
Jul 16, 2025	Grant or award from the company Stock option (right to buy)	+197,285			197,285 direct	Filing · EDGAR
Jul 15, 2025	Gift	−10,000			232,179 direct	Filing · EDGAR
Jul 15, 2025	Gift	−10,000			222,179 direct	Filing · EDGAR
Jul 15, 2025	Gift	−10,000			212,179 direct	Filing · EDGAR
Jul 15, 2025	Gift	−10,000			202,179 direct	Filing · EDGAR
Jul 14, 2025	Open-market or private purchase	+100,000	$9.11	$911K	242,179 direct	Filing · EDGAR
Jun 5, 2025	Sale under a 10b5-1 plan	−4,060	$13.35	$54K	142,179 direct	Filing · EDGAR
Mar 5, 2025	Sale under a 10b5-1 plan	−4,061	$11.83	$48K	146,239 direct	Filing · EDGAR
Dec 4, 2024	Grant or award from the company	+145,300			150,300 direct	Filing · EDGAR
Dec 4, 2024	Grant or award from the company Stock option (right to buy)	+232,100			232,100 direct	Filing · EDGAR
Sep 4, 2024	Open-market or private purchase	+800	$32.57	$26K	800 By Trust #1	Filing · EDGAR
Sep 4, 2024	Open-market or private purchase	+7,200	$33.09	$238K	8,000 By Trust #1	Filing · EDGAR
Sep 4, 2024	Open-market or private purchase	+800	$32.57	$26K	800 By Trust #2	Filing · EDGAR
Sep 4, 2024	Open-market or private purchase	+7,200	$33.09	$238K	8,000 By Trust #2	Filing · EDGAR
Sep 4, 2024	Open-market or private purchase	+800	$32.57	$26K	800 By Trust #3	Filing · EDGAR
Sep 4, 2024	Open-market or private purchase	+7,200	$33.09	$238K	8,000 By Trust #3	Filing · EDGAR
Sep 4, 2024	Open-market or private purchase	+800	$32.57	$26K	800 By Trust #4	Filing · EDGAR
Sep 4, 2024	Open-market or private purchase	+7,200	$33.09	$238K	8,000 By Trust #4	Filing · EDGAR
Mar 25, 2024	Grant or award from the company Stock Option (Right to Buy)	+679,853			679,853 direct	Filing · EDGAR

Sigilon Therapeutics Director · filings 2020 to 2023

Date	Transaction	Shares	Price	Value	Held after	Source
Aug 11, 2023	Returned to the company	−341			0 direct	Filing · EDGAR
Aug 11, 2023	Returned to the company Stock Option (Right to Buy)	−683	$6.64	$5K	0 direct	Filing · EDGAR
Aug 11, 2023	Returned to the company Stock Option (Right to Buy)	−683	$5.00	$3K	0 direct	Filing · EDGAR
May 19, 2023	Grant or award from the company Stock Option (Right to Buy)	+8,888			8,888 direct	Filing · EDGAR
May 26, 2022	Grant or award from the company Stock Option (Right to Buy)	+8,888			8,888 direct	Filing · EDGAR
Jun 24, 2021	Grant or award from the company Stock Option (Right to Buy)	+8,888	$9.97	$89K	8,888 direct	Filing · EDGAR
Dec 8, 2020	Derivative converted	+4,444			4,444 See Footnote	Filing · EDGAR
Dec 8, 2020	Derivative converted Series B-1 Convertible Preferred Stock	−4,444			0 See Footnote	Filing · EDGAR

Repligen Director · filings 2013 to 2020 · sold $4.1M

Date	Transaction	Shares	Price	Value	Held after	Source
Mar 24, 2020	Open-market or private sale	−1,858	$96.72	$180K	923 direct	Filing · EDGAR
Mar 18, 2020	Option or RSU exercised or converted	+14,000	$12.91	$181K	16,781 direct	Filing · EDGAR
Mar 18, 2020	Option or RSU exercised or converted	+3,632	$41.19	$150K	20,413 direct	Filing · EDGAR
Mar 18, 2020	Option or RSU exercised or converted	+3,366	$26.12	$88K	23,779 direct	Filing · EDGAR
Mar 18, 2020	Option or RSU exercised or converted	+2,434	$38.76	$94K	26,213 direct	Filing · EDGAR
Mar 18, 2020	Option or RSU exercised or converted	+3,304	$42.07	$139K	29,517 direct	Filing · EDGAR
Mar 18, 2020	Open-market or private sale	−24,533	$95.13	$2.3M	4,984 direct	Filing · EDGAR
Mar 18, 2020	Open-market or private sale	−1,187	$96.45	$114K	3,797 direct	Filing · EDGAR
Mar 18, 2020	Open-market or private sale	−1,016	$97.17	$99K	2,781 direct	Filing · EDGAR
Mar 18, 2020	Option or RSU exercised or converted Stock Option (Right to Buy)	−14,000			0 direct	Filing · EDGAR
Mar 18, 2020	Option or RSU exercised or converted Stock Option (Right to Buy)	−3,632			0 direct	Filing · EDGAR
Mar 18, 2020	Option or RSU exercised or converted Stock Option (Right to Buy)	−3,366			0 direct	Filing · EDGAR
Mar 18, 2020	Option or RSU exercised or converted Stock Option (Right to Buy)	−2,434			0 direct	Filing · EDGAR
Mar 18, 2020	Option or RSU exercised or converted Stock Option (Right to Buy)	−3,304			0 direct	Filing · EDGAR
Mar 4, 2020	Option or RSU exercised or converted	+10,000	$12.91	$129K	12,781 direct	Filing · EDGAR
Mar 4, 2020	Open-market or private sale	−10,000	$93.39	$934K	2,781 direct	Filing · EDGAR
Mar 4, 2020	Option or RSU exercised or converted Stock Option (Right to Buy)	−10,000			14,000 direct	Filing · EDGAR
Feb 24, 2020	Open-market or private sale	−100	$94.85	$9K	7,136 direct	Filing · EDGAR
Feb 24, 2020	Open-market or private sale	−4,355	$92.76	$404K	2,781 direct	Filing · EDGAR
May 15, 2019	Grant or award from the company	+923			7,236 direct	Filing · EDGAR
May 15, 2019	Grant or award from the company Stock Option (Right to Buy)	+2,109			2,109 direct	Filing · EDGAR
May 16, 2018	Grant or award from the company	+1,486			6,313 direct	Filing · EDGAR
May 16, 2018	Grant or award from the company Stock Option (Right to Buy)	+3,304			3,304 direct	Filing · EDGAR
May 18, 2017	Grant or award from the company	+1,206			4,827 direct	Filing · EDGAR
May 18, 2017	Grant or award from the company Stock Option (Right to Buy)	+2,434			2,434 direct	Filing · EDGAR
May 11, 2016	Grant or award from the company	+1,763			3,621 direct	Filing · EDGAR
May 11, 2016	Grant or award from the company Stock Option (Right to Buy)	+3,366			3,366 direct	Filing · EDGAR
May 21, 2015	Grant or award from the company	+1,858			1,858 direct	Filing · EDGAR
May 21, 2015	Grant or award from the company Stock Option (Right to Buy)	+3,632			3,632 direct	Filing · EDGAR
Nov 15, 2013	Grant or award from the company Stock Option (Right to Buy)	+24,000			24,000 direct	Filing · EDGAR

Bioverativ Chief Executive Officer · filings 2016 to 2018

Date	Transaction	Shares	Price	Value	Held after	Source
Mar 8, 2018	Returned to the company	−185,094	$0.00	$185	0 direct	Filing · EDGAR
Mar 8, 2018	Returned to the company Restricted Stock Units	−136,364			0 direct	Filing · EDGAR
Mar 8, 2018	Returned to the company Restricted Stock Units	−48,678			0 direct	Filing · EDGAR
Mar 8, 2018	Returned to the company Non-Qualified Stock Option	−48,230			0 direct	Filing · EDGAR
Mar 8, 2018	Returned to the company Non-Qualified Stock Option	−387,366			0 direct	Filing · EDGAR
Mar 8, 2018	Returned to the company Non-Qualified Stock Option	−193,683			0 direct	Filing · EDGAR
Feb 23, 2018	Shares withheld for tax or exercise price	−5,794	$104.74	$607K	185,094 direct	Filing · EDGAR
Feb 22, 2018	Shares withheld for tax or exercise price	−13,973	$104.30	$1.5M	190,888 direct	Filing · EDGAR
Feb 14, 2018	Option or RSU exercised or converted	+24,339			215,680 direct	Filing · EDGAR
Feb 14, 2018	Shares withheld for tax or exercise price	−10,819	$103.52	$1.1M	204,861 direct	Filing · EDGAR
Feb 14, 2018	Option or RSU exercised or converted Restricted Stock Units	−24,339			48,678 direct	Filing · EDGAR
Feb 11, 2018	Option or RSU exercised or converted	+18,381	$9.53	$175K	199,013 direct	Filing · EDGAR
Feb 11, 2018	Shares withheld for tax or exercise price	−7,672	$103.05	$791K	191,341 direct	Filing · EDGAR
Feb 11, 2018	Option or RSU exercised or converted Non-Qualified Stock Option	−18,381			0 direct	Filing · EDGAR
Jan 31, 2018	Grant or award from the company Restricted Stock Units	+136,364			136,364 direct	Filing · EDGAR
Mar 31, 2017	Shares withheld for tax or exercise price	−8,416	$54.46	$458K	180,632 direct	Filing · EDGAR
Feb 28, 2017	Grant or award from the company	+211,679			226,979 direct	Filing · EDGAR
Feb 28, 2017	Shares withheld for tax or exercise price	−3,404	$43.42	$148K	223,575 direct	Filing · EDGAR
Feb 28, 2017	Shares withheld for tax or exercise price	−3,383	$49.56	$168K	220,192 direct	Filing · EDGAR
Feb 28, 2017	Shares withheld for tax or exercise price	−8,355	$47.76	$399K	211,837 direct	Filing · EDGAR
Feb 28, 2017	Shares withheld for tax or exercise price	−6,986	$43.42	$303K	204,851 direct	Filing · EDGAR
Feb 28, 2017	Shares withheld for tax or exercise price	−2,641	$49.56	$131K	202,210 direct	Filing · EDGAR
Feb 28, 2017	Shares withheld for tax or exercise price	−6,436	$47.76	$307K	195,774 direct	Filing · EDGAR
Feb 28, 2017	Shares withheld for tax or exercise price	−6,726	$43.42	$292K	189,048 direct	Filing · EDGAR
Feb 28, 2017	Grant or award from the company Non-Qualified Stock Option	+48,230			48,230 direct	Filing · EDGAR
Feb 28, 2017	Grant or award from the company Non-Qualified Stock Option	+18,381			18,381 direct	Filing · EDGAR
Feb 14, 2017	Grant or award from the company Non-Qualified Stock Option	+193,683			193,683 direct	Filing · EDGAR
Feb 14, 2017	Grant or award from the company Non-Qualified Stock Option	+387,366			387,366 direct	Filing · EDGAR
Feb 14, 2017	Grant or award from the company Restricted Stock Units	+73,017			73,017 direct	Filing · EDGAR

Biogen EVP Pharmaceutical Oper & Tech · filings 2010 to 2016 · sold $10.7M

Date	Transaction	Shares	Price	Value	Held after	Source
Apr 1, 2016	Grant or award from the company	+8,444			39,045.24 direct	Filing · EDGAR
Feb 23, 2016	Option or RSU exercised or converted	+810			30,898.39 direct	Filing · EDGAR
Feb 23, 2016	Shares withheld for tax or exercise price	−382	$258.99	$99K	30,516.39 direct	Filing · EDGAR
Feb 23, 2016	Option or RSU exercised or converted Restricted Stock Unit	−810			6,450 direct	Filing · EDGAR
Feb 23, 2016	Other acquisition or disposition (see the filing) Restricted Stock Unit	−1,608			4,842 direct	Filing · EDGAR
Feb 22, 2016	Grant or award from the company Restricted Stock Unit	+11,850			11,850 direct	Filing · EDGAR
Feb 12, 2016	Option or RSU exercised or converted	+1,052			29,394.39 direct	Filing · EDGAR
Feb 12, 2016	Shares withheld for tax or exercise price	−495	$247.22	$122K	28,899.39 direct	Filing · EDGAR
Feb 12, 2016	Option or RSU exercised or converted	+2,246			31,145.39 direct	Filing · EDGAR
Feb 12, 2016	Shares withheld for tax or exercise price	−1,057	$247.22	$261K	30,088.39 direct	Filing · EDGAR
Feb 12, 2016	Option or RSU exercised or converted Restricted Stock Unit	−1,052			3,842 direct	Filing · EDGAR
Feb 12, 2016	Option or RSU exercised or converted Restricted Stock Unit	−2,246			2,249 direct	Filing · EDGAR
Feb 12, 2016	Other acquisition or disposition (see the filing) Restricted Stock Unit	−1,394			2,448 direct	Filing · EDGAR
Feb 8, 2016	Option or RSU exercised or converted	+4,026			29,666.39 direct	Filing · EDGAR
Feb 8, 2016	Shares withheld for tax or exercise price	−1,324	$250.77	$332K	28,342.39 direct	Filing · EDGAR
Feb 8, 2016	Option or RSU exercised or converted Restricted Stock Unit	−4,026			0 direct	Filing · EDGAR
Mar 25, 2015	Option or RSU exercised or converted	+2,175	$72.87	$158K	34,686.29 direct	Filing · EDGAR
Mar 25, 2015	Option or RSU exercised or converted	+2,891	$60.56	$175K	37,577.29 direct	Filing · EDGAR
Mar 25, 2015	Sale under a 10b5-1 plan	−12,010	$449.06	$5.4M	25,567.29 direct	Filing · EDGAR
Mar 25, 2015	Option or RSU exercised or converted Stock Option (Right to Buy)	−2,175			0 direct	Filing · EDGAR
Mar 25, 2015	Option or RSU exercised or converted Stock Option (Right to Buy)	−2,891			2,892 direct	Filing · EDGAR
Feb 23, 2015	Grant or award from the company Restricted Stock Unit	+7,260			7,260 direct	Filing · EDGAR
Feb 12, 2015	Option or RSU exercised or converted	+2,246			32,780.29 direct	Filing · EDGAR
Feb 12, 2015	Shares withheld for tax or exercise price	−1,058	$392.11	$415K	31,722.29 direct	Filing · EDGAR
Feb 12, 2015	Option or RSU exercised or converted	+1,492			33,214.29 direct	Filing · EDGAR
Feb 12, 2015	Shares withheld for tax or exercise price	−703	$392.11	$276K	32,511.29 direct	Filing · EDGAR
Feb 12, 2015	Option or RSU exercised or converted Restricted Stock Unit	−2,246			4,495 direct	Filing · EDGAR
Feb 12, 2015	Option or RSU exercised or converted Restricted Stock Unit	−1,492			5,848 direct	Filing · EDGAR
Feb 12, 2015	Other acquisition or disposition (see the filing) Restricted Stock Unit	−954			4,894 direct	Filing · EDGAR
Feb 9, 2015	Option or RSU exercised or converted	+4,691			32,744.29 direct	Filing · EDGAR
Feb 9, 2015	Shares withheld for tax or exercise price	−2,210	$396.88	$877K	30,534.29 direct	Filing · EDGAR
Feb 9, 2015	Option or RSU exercised or converted Restricted Stock Unit	−4,691			0 direct	Filing · EDGAR
Feb 8, 2015	Option or RSU exercised or converted	+4,023			29,590.29 direct	Filing · EDGAR
Feb 8, 2015	Shares withheld for tax or exercise price	−1,537	$402.00	$618K	28,053.29 direct	Filing · EDGAR
Feb 8, 2015	Option or RSU exercised or converted Restricted Stock Unit	−4,023			4,026 direct	Filing · EDGAR
Feb 23, 2014	Option or RSU exercised or converted	+2,598			26,706.11 direct	Filing · EDGAR
Feb 23, 2014	Shares withheld for tax or exercise price	−1,228	$347.11	$426K	25,478.11 direct	Filing · EDGAR
Feb 23, 2014	Option or RSU exercised or converted Restricted Stock Unit	−2,598			0 direct	Filing · EDGAR
Feb 12, 2014	Option or RSU exercised or converted	+2,246			25,167.11 direct	Filing · EDGAR
Feb 12, 2014	Shares withheld for tax or exercise price	−1,059	$323.04	$342K	24,108.11 direct	Filing · EDGAR
Feb 12, 2014	Option or RSU exercised or converted Restricted Stock Unit	−2,246			6,741 direct	Filing · EDGAR
Feb 12, 2014	Grant or award from the company Restricted Stock Unit	+7,340			7,340 direct	Filing · EDGAR
Feb 9, 2014	Option or RSU exercised or converted	+4,691			25,133.11 direct	Filing · EDGAR
Feb 9, 2014	Shares withheld for tax or exercise price	−2,212	$315.54	$698K	22,921.11 direct	Filing · EDGAR
Feb 9, 2014	Option or RSU exercised or converted Restricted Stock Unit	−4,691			4,691 direct	Filing · EDGAR
Feb 8, 2014	Option or RSU exercised or converted	+4,023			21,883.11 direct	Filing · EDGAR
Feb 8, 2014	Shares withheld for tax or exercise price	−1,441	$315.54	$455K	20,442.11 direct	Filing · EDGAR
Feb 8, 2014	Option or RSU exercised or converted Restricted Stock Unit	−4,023			8,049 direct	Filing · EDGAR
Nov 25, 2013	Gift	−200			17,860.11 direct	Filing · EDGAR
May 3, 2013	Shares withheld for tax or exercise price	−866	$218.85	$190K	18,060.11 direct	Filing · EDGAR
Feb 23, 2013	Option or RSU exercised or converted	+2,598			19,986.44 direct	Filing · EDGAR
Feb 23, 2013	Shares withheld for tax or exercise price	−1,227	$164.40	$202K	18,759.44 direct	Filing · EDGAR
Feb 23, 2013	Option or RSU exercised or converted Restricted Stock Unit	−2,598			2,598 direct	Filing · EDGAR
Feb 12, 2013	Grant or award from the company Restricted Stock Unit	+8,987			8,987 direct	Filing · EDGAR
Feb 9, 2013	Option or RSU exercised or converted	+4,692			19,224.44 direct	Filing · EDGAR
Feb 9, 2013	Shares withheld for tax or exercise price	−1,836	$164.44	$302K	17,388.44 direct	Filing · EDGAR
Feb 9, 2013	Option or RSU exercised or converted Restricted Stock Unit	−4,692			9,382 direct	Filing · EDGAR
Feb 8, 2013	Option or RSU exercised or converted	+3,487			15,665.44 direct	Filing · EDGAR
Feb 8, 2013	Shares withheld for tax or exercise price	−1,133	$164.44	$186K	14,532.44 direct	Filing · EDGAR
Feb 8, 2013	Option or RSU exercised or converted Restricted Stock Unit	−3,487			12,608 direct	Filing · EDGAR

54 earlier transactions are in the filing list below.

All 90 Forms 3, 4, 5 and 144

Filed	Form	Company	Links
Sep 8, 2026	Form 144	Dyne Therapeutics DYN	Filing · EDGAR
Sep 8, 2026	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Aug 17, 2026	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Aug 13, 2026	Form 144	Dyne Therapeutics DYN	Filing · EDGAR
Jun 17, 2026	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Jun 16, 2026	Form 144	Dyne Therapeutics DYN	Filing · EDGAR
May 14, 2026	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
May 13, 2026	Form 144	Dyne Therapeutics DYN	Filing · EDGAR
Mar 6, 2026	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Mar 5, 2026	Form 144	Dyne Therapeutics DYN	Filing · EDGAR
Feb 17, 2026	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Dec 5, 2025	Form 144	Dyne Therapeutics DYN	Filing · EDGAR
Dec 5, 2025	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Sep 9, 2025	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Sep 5, 2025	Form 144	Dyne Therapeutics DYN	Filing · EDGAR
Jul 18, 2025	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Jul 15, 2025	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Jun 6, 2025	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Jun 5, 2025	Form 144	Dyne Therapeutics DYN	Filing · EDGAR
Mar 7, 2025	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Mar 5, 2025	Form 144	Dyne Therapeutics DYN	Filing · EDGAR
Dec 6, 2024	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Sep 4, 2024	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Apr 4, 2024	Form 3/A	Dyne Therapeutics DYN	Filing · EDGAR
Mar 27, 2024	Form 4	Dyne Therapeutics DYN	Filing · EDGAR
Mar 27, 2024	Form 3	Dyne Therapeutics DYN	Filing · EDGAR
Aug 11, 2023	Form 4	Sigilon Therapeutics	Filing · EDGAR
May 22, 2023	Form 4	Sigilon Therapeutics	Filing · EDGAR
May 27, 2022	Form 4	Sigilon Therapeutics	Filing · EDGAR
Jun 28, 2021	Form 4	Sigilon Therapeutics	Filing · EDGAR
Dec 10, 2020	Form 4	Sigilon Therapeutics	Filing · EDGAR
Dec 3, 2020	Form 3	Sigilon Therapeutics	Filing · EDGAR
Mar 26, 2020	Form 4	Repligen	Filing · EDGAR
Mar 20, 2020	Form 4	Repligen	Filing · EDGAR
Mar 5, 2020	Form 4	Repligen	Filing · EDGAR
Feb 26, 2020	Form 4	Repligen	Filing · EDGAR
May 17, 2019	Form 4	Repligen	Filing · EDGAR
May 17, 2018	Form 4	Repligen	Filing · EDGAR
Mar 8, 2018	Form 4	Bioverativ	Filing · EDGAR
Feb 26, 2018	Form 4	Bioverativ	Filing · EDGAR
Feb 15, 2018	Form 4	Bioverativ	Filing · EDGAR
Feb 13, 2018	Form 4	Bioverativ	Filing · EDGAR
Feb 2, 2018	Form 4	Bioverativ	Filing · EDGAR
May 22, 2017	Form 4	Repligen	Filing · EDGAR
Apr 3, 2017	Form 4	Bioverativ	Filing · EDGAR
Mar 27, 2017	Form 4/A	Bioverativ	Filing · EDGAR
Mar 2, 2017	Form 4	Bioverativ	Filing · EDGAR
Feb 16, 2017	Form 4	Bioverativ	Filing · EDGAR
Dec 22, 2016	Form 3	Bioverativ	Filing · EDGAR
May 13, 2016	Form 4	Repligen	Filing · EDGAR
Apr 5, 2016	Form 4	Biogen	Filing · EDGAR
Feb 25, 2016	Form 4	Biogen	Filing · EDGAR
Feb 24, 2016	Form 4	Biogen	Filing · EDGAR
Feb 17, 2016	Form 4	Biogen	Filing · EDGAR
Feb 9, 2016	Form 4	Biogen	Filing · EDGAR
May 26, 2015	Form 4	Repligen	Filing · EDGAR
Mar 26, 2015	Form 4	Biogen	Filing · EDGAR
Feb 25, 2015	Form 4	Biogen	Filing · EDGAR
Feb 17, 2015	Form 4	Biogen	Filing · EDGAR
Feb 10, 2015	Form 4	Biogen	Filing · EDGAR
Feb 25, 2014	Form 4	Biogen	Filing · EDGAR
Feb 14, 2014	Form 4	Biogen	Filing · EDGAR
Feb 11, 2014	Form 4	Biogen	Filing · EDGAR
Dec 4, 2013	Form 4	Biogen	Filing · EDGAR
Nov 19, 2013	Form 4	Repligen	Filing · EDGAR
Nov 19, 2013	Form 3	Repligen	Filing · EDGAR
May 7, 2013	Form 4	Biogen	Filing · EDGAR
Feb 26, 2013	Form 4	Biogen	Filing · EDGAR
Feb 14, 2013	Form 4	Biogen	Filing · EDGAR
Feb 12, 2013	Form 4	Biogen	Filing · EDGAR
May 4, 2012	Form 4	Biogen	Filing · EDGAR
Feb 27, 2012	Form 4	Biogen	Filing · EDGAR
Feb 13, 2012	Form 4	Biogen	Filing · EDGAR
Feb 10, 2012	Form 4	Biogen	Filing · EDGAR
Nov 3, 2011	Form 4	Biogen	Filing · EDGAR
May 4, 2011	Form 4	Biogen	Filing · EDGAR
Apr 25, 2011	Form 4	Biogen	Filing · EDGAR
Apr 15, 2011	Form 4	Biogen	Filing · EDGAR
Apr 13, 2011	Form 4	Biogen	Filing · EDGAR
Apr 1, 2011	Form 4	Biogen	Filing · EDGAR
Mar 3, 2011	Form 4	Biogen	Filing · EDGAR
Feb 28, 2011	Form 4	Biogen	Filing · EDGAR
Feb 25, 2011	Form 4	Biogen	Filing · EDGAR
Feb 18, 2011	Form 4	Biogen	Filing · EDGAR
Feb 15, 2011	Form 4	Biogen	Filing · EDGAR
Feb 11, 2011	Form 4	Biogen	Filing · EDGAR
Nov 10, 2010	Form 4	Biogen	Filing · EDGAR
Nov 3, 2010	Form 4	Biogen	Filing · EDGAR
Oct 29, 2010	Form 4	Biogen	Filing · EDGAR
Aug 10, 2010	Form 3	Biogen	Filing · EDGAR

Every figure is as filed with the SEC on Forms 3, 4, 5 and 144. Holdings are the amounts reported after each person's latest filing at each company and can be out of date. Matching a Form 144 notice to Form 4 sales is SEC Tracker's inference from owner, company, dates and share counts, not something the filings state. Not investment advice. Not affiliated with the U.S. SEC.