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Disclosery

RTW INVESTMENTS, LP: MASI position timeline

Available 13F reports, 13D and 13G stakes and each Form 3, 4 and 5 line of RTW INVESTMENTS, LP on MASI, newest first. How the timeline and the estimate are built.

RTW INVESTMENTS, LP held 0 MASI shares at 2026-03-31 per its 13F-HR filed 2026-05-15.

the latest 13F is the newest step

  1. period ended2026-03-31
    13F 0 shares
    Change vs previous 13F -683,294 shares

    13F-HR 0001493215-26-000130 filed by RTW INVESTMENTS, LP
    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 683,294 shares
    Change vs previous 13F 0 shares

    0.89% of the 13F portfolio, value $88,869,218.

    13F-HR 0001493215-26-000060 filed by RTW INVESTMENTS, LP
    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 683,294 shares
    Change vs previous 13F 0 shares

    1.24% of the 13F portfolio, value $100,820,030.

    13F-HR 0001493215-25-000054 filed by RTW INVESTMENTS, LP
    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 683,294 shares
    Change vs previous 13F 0 shares

    1.64% of the 13F portfolio, value $114,943,717.

    13F-HR 0001493215-25-000007 filed by RTW INVESTMENTS, LP
    Filed (acceptance time not in the bulk data set), ingested

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

  5. period ended2025-03-31
    13F 683,294 shares
    Change vs previous 13F 0 shares

    1.74% of the 13F portfolio, value $113,836,780.

    13F-HR 0001493215-25-000003 filed by RTW INVESTMENTS, LP
    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 683,294 shares
    Change vs previous 13F -779,106 shares

    1.71% of the 13F portfolio, value $112,948,498.

    13F-HR 0001493152-25-006608 filed by RTW INVESTMENTS, LP
    Filed (acceptance time not in the bulk data set), ingested

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

  7. period ended2024-09-30
    13F 1,462,400 shares
    Change vs previous 13F not available

    2.82% of the 13F portfolio, value $194,981,792.

    13F-HR 0001493152-24-045409 filed by RTW INVESTMENTS, LP
    Filed (acceptance time not in the bulk data set), ingested

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