RA Capital Management Increases Stake in Artiva Biotherapeutics With $412,000 Share Purchase

RA Capital's Multi-Vehicle Ownership Structure in Artiva

The disclosure reveals the complex ownership architecture through which RA Capital maintains its significant stake in Artiva Biotherapeutics. Rather than holding shares directly through a single entity, RA Capital Management, L.P. serves as the investment manager for multiple fund vehicles and accounts that collectively maintain beneficial ownership of the company's common stock. The filing identifies four separate holdings: approximately 17.3 million shares held directly by RA Capital Healthcare Fund LP, 264,571 shares held by RA Capital Nexus Fund L.P., 826,832 shares held by RA Capital Nexus Fund III L.P., and 68,320 shares held in a separately managed account.

This multi-vehicle structure is common among institutional investment managers and allows for diversified capital deployment across different fund strategies and investor bases. The accompanying footnotes to the disclosure clarify that RA Capital Management GP, LLC serves as the general partner of the adviser and is managed by Dr. Peter Kolchinsky and Mr. Rajeev Shah as managing members. All reporting parties, including the adviser, its general partner, the individual funds, and the two managing members, filed the disclosure jointly on July 28, 2026, reflecting the interconnected nature of these ownership vehicles.

Transaction Details and Share Purchase Mechanics

The July 24, 2026 share purchase involved the acquisition of 41,319 shares of Artiva common stock at a weighted average price of $9.99 per share. The filing indicates that this transaction actually consisted of multiple purchases executed on the same date, with individual share prices ranging from $9.96 to $10.00 inclusive. This narrow price range suggests the transactions occurred within a relatively compressed timeframe or market window, though the filing does not specify the exact timing of each individual purchase or the number of shares acquired at each distinct price point.

The reporting parties undertake to provide full information regarding the number of shares purchased at each separate price within the disclosed range to the issuer, security holders, or the Securities and Exchange Commission upon request. The transaction code "P" in the filing designates this as an open market purchase of equity securities. The weighted average price methodology allows RA Capital to report multiple transactions as a single line item while maintaining full transparency through the ability to provide granular transaction details to interested parties.

Board Representation and Governance Involvement

The disclosure includes an important governance notation: Laura Stoppel, a partner at RA Capital Management, serves on Artiva Biotherapeutics' board of directors. This board seat reflects RA Capital's strategic involvement in the company beyond passive shareholding and suggests active engagement in corporate governance matters. The presence of a RA Capital partner on the board, combined with the substantial beneficial ownership position, positions the investment firm as a material stakeholder in the company's strategic direction and operational oversight.

The board representation may facilitate coordination between RA Capital's investment thesis and the company's strategic initiatives, though the filing itself does not elaborate on specific board activities or the nature of RA Capital's engagement with management. This governance participation is consistent with RA Capital's profile as an active healthcare venture and growth equity investor focused on biotherapeutic companies.

Beneficial Ownership Concentration Among RA Capital Entities

The combined beneficial ownership position disclosed across all RA Capital reporting entities totals approximately 18.4 million shares of Artiva common stock held indirectly. This substantial shareholding encompasses the new 41,319 shares acquired on July 24, 2026, plus the existing positions held across the four investment vehicles. The filing structure clarifies that while each entity maintains formal beneficial ownership of its respective shares, all parties disclaim beneficial ownership except to the extent of their pecuniary interest—a standard provision that acknowledges the investment management relationship while preserving appropriate liability and control clarity.

The distribution across multiple funds and managed accounts suggests that Artiva represents a meaningful position across RA Capital's healthcare investment portfolio. Investors analyzing institutional ownership should note that these shares are held on behalf of various fund investors rather than representing a single concentrated personal stake, which may influence voting behavior and long-term holding intentions across economic cycles and market conditions.

Form 4 Filing Timing and Regulatory Requirements

The transaction occurred on July 24, 2026, but was reported on July 28, 2026, consistent with Securities Exchange Act Section 16(a) requirements that officers, directors, and ten-percent beneficial owners report trades within two business days of execution. RA Capital Management and its affiliated entities and individual managers all checked the "Director" and "10% Owner" boxes on the disclosure form, confirming their status as reporting insiders subject to Section 16 requirements. The timely filing suggests compliance with regulatory reporting deadlines.

The filing was executed by multiple signatories reflecting the various reporting persons involved: Peter Kolchinsky as manager of RA Capital Management L.P. and as manager of the general partners of the affiliated funds, and Rajeev Shah in his individual capacity as a managing member of RA Capital Management GP, LLC. This multi-signatory approach ensures that each reporting person acknowledges the accuracy and completeness of the disclosure with respect to their beneficial holdings and transactions.

No Derivative Securities Reported in Transaction

The disclosure includes Table II for reporting derivative securities such as options, warrants, puts, calls, or convertible securities, but this section contains no entries. This indicates that the July 24, 2026 transaction involved only direct common stock purchases with no derivative instruments acquired or exercised in connection with this activity. The absence of derivative activity suggests that RA Capital's current investment position in Artiva consists of straightforward equity ownership without optionality strategies or hedging instruments reflected in this particular report.

Investors should note that the absence of reported derivatives in this filing does not preclude the existence of such instruments at other times or through different structures, but reflects only the transactions and holdings being reported on July 28, 2026.

Investment Price Context and Market Conditions

The purchase prices ranging from $9.96 to $10.00 per share reflect the market valuation at which RA Capital was willing to deploy approximately $412,000 of capital in Artiva stock on July 24, 2026. This narrow price band provides limited insight into broader market sentiment or volatility surrounding the company on that date, but the execution of purchases within this range suggests relatively stable trading conditions during the transaction period. The weighted average of $9.99 falls near the midpoint of the disclosed range, consistent with balanced execution across the multiple individual transactions.

The filing itself contains no forward-looking statements, guidance, or management commentary regarding the company's operations, pipeline, financial condition, or prospects. The share purchase price should not be interpreted as any statement regarding intrinsic value or fair value by RA Capital, but rather simply as the market price at which shares were available for purchase on the execution date.

Expanded Insider Ownership Pool and Strategic Intent

The July 24 purchase represents new acquisition activity by RA Capital in Artiva, adding to its existing substantial position. While the filing does not provide explicit commentary on the rationale for the purchase, the timing and size suggest deliberate portfolio management by the healthcare investment specialist. The decision to add shares at current market prices, even in a relatively modest quantity relative to existing holdings, may reflect RA Capital's confidence in the company or its assessment of valuation relative to longer-term investment objectives.

The filing does not disclose RA Capital's total investment capacity, the size of its healthcare fund vehicles, Artiva's weight within those portfolios, or any forward-looking trading plans. These details, if material to investor decision-making, would need to be obtained from separate RA Capital disclosures or fund documents rather than from this Section 16 transaction report.

Regulatory Classification and Reporting Person Status

All reporting persons checked the applicable boxes confirming their status as either directors, ten-percent beneficial owners, or both. RA Capital Management L.P., RA Capital Healthcare Fund LP, RA Capital Nexus Fund L.P., RA Capital Nexus Fund III L.P., Dr. Peter Kolchinsky, and Mr. Rajeev Shah all qualified as 10% owners under Securities Exchange Act Section 13(d) and/or held director positions. Only RA Capital Nexus Fund L.P. checked the director box without checking the 10% owner box in its respective section, suggesting a possible difference in beneficial ownership percentage versus governance participation between that fund and the others, though the footnotes clarify all funds hold shares through the management structure.

The joint filing approach, while potentially complex in structure, consolidates multiple related reporting persons' transactions and holdings in a single document, enhancing transparency for investors reviewing insider activity in NASDAQ-listed securities. The filing availability on SEC EDGAR provides public access to these material ownership and transaction data.