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Disclosery

Atika Capital Management LLC: INSM position timeline

Available 13F reports, 13D and 13G stakes and each Form 3, 4 and 5 line of Atika Capital Management LLC on INSM, newest first. How the timeline and the estimate are built.

Atika Capital Management LLC held 0 INSM shares at 2026-03-31 per its 13F-HR filed 2026-05-14.

the latest 13F is the newest step

  1. period ended2026-03-31
    13F 0 shares
    Change vs previous 13F -77,200 shares

    13F-HR 0001214659-26-006119 filed by Atika Capital Management LLC
    Filed (acceptance time not in the bulk data set), ingested

    Acceptance time not in the bulk data set (spec §4.2).

    Exited: the 13F for this period no longer lists the position.

  2. period ended2025-12-31
    13F 77,200 shares
    Change vs previous 13F -17,800 shares

    1.87% of the 13F portfolio, value $13,435,888.

    13F-HR 0001214659-26-001658 filed by Atika Capital Management LLC
    Filed (acceptance time not in the bulk data set), ingested

    Acceptance time not in the bulk data set (spec §4.2).

  3. period ended2025-09-30
    13F 95,000 shares
    Change vs previous 13F +95,000 shares

    1.17% of the 13F portfolio, value $13,680,950.

    13F-HR 0001214659-25-016379 filed by Atika Capital Management LLC
    Filed (acceptance time not in the bulk data set), ingested

    Acceptance time not in the bulk data set (spec §4.2).

  4. period ended2025-06-30
    13F 0 shares
    Change vs previous 13F -96,000 shares

    13F-HR 0001214659-25-011890 filed by Atika Capital Management LLC
    Filed (acceptance time not in the bulk data set), ingested

    Acceptance time not in the bulk data set (spec §4.2).

    Exited: the 13F for this period no longer lists the position.

  5. period ended2025-03-31
    13F 96,000 shares
    Change vs previous 13F +96,000 shares

    1.12% of the 13F portfolio, value $7,323,839.

    13F-HR 0001214659-25-007540 filed by Atika Capital Management LLC
    Filed (acceptance time not in the bulk data set), ingested

    Acceptance time not in the bulk data set (spec §4.2).

  6. period ended2024-12-31
    13F 0 shares
    Change vs previous 13F -62,000 shares

    13F-HR 0001214659-25-002515 filed by Atika Capital Management LLC
    Filed (acceptance time not in the bulk data set), ingested

    Acceptance time not in the bulk data set (spec §4.2).

    Exited: the 13F for this period no longer lists the position.

  7. period ended2024-09-30
    13F 62,000 shares
    Change vs previous 13F not available

    0.48% of the 13F portfolio, value $4,526,000.

    13F-HR 0001214659-24-018802 filed by Atika Capital Management LLC
    Filed (acceptance time not in the bulk data set), ingested

    Acceptance time not in the bulk data set (spec §4.2).