Artiva (ARTV) 10% Holder RA Capital Buys $2.58M Stock

What Happened
RA Capital Management, L.P. (a reported 10% owner) acquired a total of 264,586 shares of Artiva Biotherapeutics (ARTV) in open-market/private purchases across July 21–23, 2026. The three purchases were: 120,582 shares @ $9.55 (≈ $1,151,558) on 2026-07-21; 84,124 shares @ $9.93 (≈ $835,351) on 2026-07-22; and 59,880 shares @ $9.96 (≈ $596,405) on 2026-07-23. Total reported outlay is about $2,583,314. These are purchases (institutional buying), which some investors view as a positive signal, though this filing alone doesn’t explain the intent.

Key Details

• Transaction type: P = Purchase (open market or private purchase).
• Dates & reported weighted-average prices: 7/21/2026 — 120,582 @ $9.55; 7/22/2026 — 84,124 @ $9.93; 7/23/2026 — 59,880 @ $9.96. Total ≈ 264,586 shares for ≈ $2.58M.
• Price ranges: filing footnotes note weighted averages; execution prices ranged roughly between $9.16 and $10.00 across the trades.
• Ownership after transaction: not specified in the excerpt provided (filing identifies RA Capital as a 10% owner).
• Filing date: 2026-07-23. The filing appears timely relative to the trade dates (no late-filing flag indicated).
• Structure notes: RA Capital is the adviser to multiple funds/accounts; several footnotes state specific shares are held directly by the Fund, Nexus Fund, Nexus Fund III, or a separately managed Account. The adviser and related parties disclaim beneficial ownership except for their pecuniary interest.
• Corporate link: Laura Stoppel, a Partner of the Adviser, serves on Artiva’s board of directors (noted in the filing).

Context

• This is institutional buying by a reported 10% holder (an investment manager buying for funds/accounts), not an individual executive trade. That distinction matters for how investors interpret insider sentiment.
• Purchases were reported as open-market/private buys (no options/exercises or gifts). The weighted-average prices and footnotes mean the trades were done in multiple executions at slightly different prices.
• The filing is factual disclosure of holdings changes and does not state motives; use it as one data point alongside other research when assessing the stock.