Form 4 for SPTX Seaport Therapeutics, Inc.

Accepted 2026-05-06 19:38:15 ET · period of report 2026-05-04 · accession 0001193125-26-209701 · SEC index · Original document

Summary rows

Aggregated the way they appear in lists: one row per insider, transaction code and security table.

X	Filed	Traded	Ticker	Insider	Title	Type	Price	Qty	Owned	ΔOwn	Value
DMI	2026-05-06 19:38	2026-05-04	SPTX	PureTech Health plc	10%	C - Cnv Deriv	—	+16.38M	16.69M	+5,416%	—
DMI	2026-05-06 19:38	2026-05-04	SPTX	PureTech Health plc	10%	C - Cnv Deriv	$0.00	-51.45M	0	-100%	$0

Purchase Sale Sale after option exercise All abbreviations

Every reported transaction

#	Table	Security	Date	Code	A/D	Shares	Price	Owned after	Own	Exercise / expiry	Underlying	Footnotes
1	Common	Common Stock	2026-05-04	C	A	12,736,014	—	13,038,493	I See footnote	—	—	(F1) Each share of Series A-1, Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date. (F2) PureTech LYT, Inc. is the record holder of all of the securities reported in this Form 4. PureTech Health LLC is the sole owner of PureTech LYT, Inc. PureTech Health plc is the sole member of PureTech Health LLC, and has the power to direct the voting and disposition of securities held by PureTech LYT, Inc. and PureTech Health LLC.
2	Common	Common Stock	2026-05-04	C	A	2,681,265	—	15,719,758	I See footnote	—	—	(F1) Each share of Series A-1, Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date. (F2) PureTech LYT, Inc. is the record holder of all of the securities reported in this Form 4. PureTech Health LLC is the sole owner of PureTech LYT, Inc. PureTech Health plc is the sole member of PureTech Health LLC, and has the power to direct the voting and disposition of securities held by PureTech LYT, Inc. and PureTech Health LLC.
3	Common	Common Stock	2026-05-04	C	A	965,255	—	16,685,013	I See footnote	—	—	(F1) Each share of Series A-1, Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date. (F2) PureTech LYT, Inc. is the record holder of all of the securities reported in this Form 4. PureTech Health LLC is the sole owner of PureTech LYT, Inc. PureTech Health plc is the sole member of PureTech Health LLC, and has the power to direct the voting and disposition of securities held by PureTech LYT, Inc. and PureTech Health LLC.
4	Derivative	Series A-1 Preferred Stock	2026-05-04	C	D	40,000,000	$0.00	0	I See footnote	— · — to —	12,736,014 Common Stock	(F1) Each share of Series A-1, Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date. (F1) Each share of Series A-1, Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date. (F1) Each share of Series A-1, Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date. (F2) PureTech LYT, Inc. is the record holder of all of the securities reported in this Form 4. PureTech Health LLC is the sole owner of PureTech LYT, Inc. PureTech Health plc is the sole member of PureTech Health LLC, and has the power to direct the voting and disposition of securities held by PureTech LYT, Inc. and PureTech Health LLC.
5	Derivative	Series A-2 Preferred Stock	2026-05-04	C	D	8,421,052	$0.00	0	I See footnote	— · — to —	2,681,265 Common Stock	(F1) Each share of Series A-1, Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date. (F1) Each share of Series A-1, Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date. (F1) Each share of Series A-1, Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date. (F2) PureTech LYT, Inc. is the record holder of all of the securities reported in this Form 4. PureTech Health LLC is the sole owner of PureTech LYT, Inc. PureTech Health plc is the sole member of PureTech Health LLC, and has the power to direct the voting and disposition of securities held by PureTech LYT, Inc. and PureTech Health LLC.
6	Derivative	Series B Preferred Stock	2026-05-04	C	D	3,031,578	$0.00	0	I See footnote	— · — to —	965,255 Common Stock	(F1) Each share of Series A-1, Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date. (F1) Each share of Series A-1, Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date. (F1) Each share of Series A-1, Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date. (F2) PureTech LYT, Inc. is the record holder of all of the securities reported in this Form 4. PureTech Health LLC is the sole owner of PureTech LYT, Inc. PureTech Health plc is the sole member of PureTech Health LLC, and has the power to direct the voting and disposition of securities held by PureTech LYT, Inc. and PureTech Health LLC.