Arch Venture Partners Xii, LLC

10% Owner

4 companies

Insider Signal Score

Good

Trades Analyzed

12M Win Rate

60.0%

Avg 3M Return

+33.1%

Avg 12M Return

+2.1%

Arch Venture Partners Xii, LLC is a 10% Owner at Prime Medicine, Inc. with holdings across 4 companies. Recent SEC Form 4 filings include 22 buys and 0 sells.

Estimated insider holdings value: $211.5M based on current market prices.

Holdings by Company

PRMEAug 1, 2025

Current Shares6.23M

Value$19.84M

Net Activity+6.23M

Bought: 6.23MSold: 0

NMRAOct 27, 2025

Current Shares6.05M

Value$10.98M

Net Activity+2.42M

Bought: 2.42MSold: 0

RAPPJun 10, 2024

Current Shares3.73M

Value$141.36M

Net Activity0

Bought: 0Sold: 0

SPTX4d ago

Current Shares2.51M

Value$39.36M

Net Activity+1.10M

Bought: 1.10MSold: 0

Transaction History

Showing 10 filings

Date	Ticker	Role	Type	Shares	Price	Value	Chg%	3M	12M
May 4, 2026	SPTX Seaport Therapeutics, Inc. Common Stock	10% Owner	Buy	1,100,000	$18.00	$19,800,000.00	+21.2%	-	-
Oct 27, 2025	NMRA Neumora Therapeutics, Inc.	10% Owner	Buy	1,915,700	$2.61	$4,999,977.00	+46.4%	-24.2%	-
Aug 1, 2025	PRME Prime Medicine, Inc.	10% Owner	Buy	3,030,300	$3.30	$9,999,990.00	+94.7%	+7.7%	-
Feb 15, 2024	PRME Prime Medicine, Inc.	10% Owner	Buy	3,200,000	$6.25	$20,000,000.00	New	-13.3%	-63.6%
Nov 14, 2023	NMRA Neumora Therapeutics, Inc.	10% Owner	Buy	35,010	$11.77	$412,139.61	+0.4%	+52.3%	-9.1%
Nov 10, 2023	NMRA Neumora Therapeutics, Inc.	10% Owner	Buy	140,605	$10.98	$1,543,563.42	+0.7%	+50.7%	+16.9%
Nov 7, 2023	NMRA Neumora Therapeutics, Inc.	10% Owner	Buy	95,694	$11.49	$1,099,944.70	+0.8%	+30.9%	+9.6%
Sep 29, 2023	NMRA Neumora Therapeutics, Inc.	10% Owner	Buy	76,511	$13.68	$1,046,848.16	+0.7%	+21.5%	-8.4%
Sep 27, 2023	NMRA Neumora Therapeutics, Inc.	10% Owner	Buy	58,504	$11.97	$700,464.24	+0.8%	+48.1%	+10.7%
Sep 25, 2023	NMRA Neumora Therapeutics, Inc.	10% Owner	Buy	100,740	$11.19	$1,127,063.95	+0.9%	+53.6%	+8.6%

Insider	Role	Shares	Value	Buys	Sells

Date	Ticker	Insider	Role	Type	Shares	Price	Value	Chg%	SEC