Updated Jul 16, 2026
ARCH Venture Partners XII, LLC has filed 1 SEC Form 4 filing across 1 company in the last 90 days — buying. Lifetime open-market purchases: $29.80M.
| Date | Ticker | Company | Code | Shares | Price | Value |
|---|---|---|---|---|---|---|
| 2026-05-04 | SPTX | Seaport Therapeutics, Inc. | P — Open-market purchase | 1.10M | $18.00 | $19.80M |
| 2026-05-04 | SPTX | Seaport Therapeutics, Inc. | J — Other acquisition / disposition | 2.68M | — | |
| 2026-05-04 | SPTX | Seaport Therapeutics, Inc. | J — Other acquisition / disposition | 2.51M | — | |
| 2025-08-01 | PRME | Prime Medicine, Inc. | P — Open-market purchase | 3.03M | $3.30 | $10.00M |
ARCH Venture Partners XII, LLC is a corporate insider — currently tracked as Insider of Seaport Therapeutics, Inc. (SPTX). InsiderAlpha tracks every SEC Form 4 filing in real time.
1 primary Form 4 filings in the last 90 days, covering 1 company.
Recorded transactions: 2 open-market purchases ($29.80M) and 0 open-market sales () across all tracked filings.
All Form 4 filings, transaction values, and 10b5-1 plan flags are listed on this page and updated in real time as new SEC EDGAR filings are processed.
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