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Flagship Ventures Fund IV, L.P.

CIK 1503559 · last filed 2020-11-25

Flagship Ventures Fund IV, L.P. is a corporate insider who has filed 6 SEC Form 4 insider transactions across 4 companies since 2016. Across all open-market trades the lifetime net is +$70.9M, making them a net buyer over the disclosed history. The firm reports its address in Cambridge, MA. 45 SEC filings were submitted jointly with Flagship Ventures Fund IV General Partner LLC.

"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.

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Disclosed Exposure

$0

Companies

4

Total Filings

6

Lifetime Open-Market Net

$70.88M

Filer Profile

Reported Address
55 CAMBRIDGE PARKWAY, 8TH FLOOR
CAMBRIDGE, MA 02142
Phone
(617) 868-1888
State of Incorporation
DE
Related Filers
Flagship Ventures Fund IV General Partner LLC — 45 joint filings, latest 2023-07-13
NOUBAR AFEYAN — 43 joint filings, latest 2023-07-13
Flagship Ventures Fund IV-Rx, L.P. — 33 joint filings, latest 2022-06-01
Edwin Kania — 26 joint filings, latest 2019-12-11
Flagship Ventures 2007 General Partner LLC — 16 joint filings, latest 2019-10-31
Flagship Ventures Fund 2007, L.P. — 16 joint filings, latest 2019-10-31
Flagship VentureLabs IV, LLC — 15 joint filings, latest 2019-05-15
Flagship Ventures Opportunities Fund I, L.P. — 13 joint filings, latest 2022-10-17
Profile details as reported on the filer's SEC submissions — for individual insiders the address is often in care of the issuer. Related filers are identified from jointly filed SEC submissions and shared reported addresses. View filings on SEC EDGAR.

Holdings By Company

Latest on-record share count from this person's most recent non-derivative Form 4 transaction in each company. Disclosed exposure = shares × current underlying price.
Symbol Role Shares Price Disclosed Exposure Lifetime OM Net Filings Latest Filed
MCRB 10%+ Owner 0 $5.72 $0 $0 1 2020-11-25
MRNA 10%+ Owner 0 $145.55 $0 $0 2 2020-08-19
Kaleido Biosciences, Inc. (KLDO) Delisted 10%+ Owner 2,560,096 $0.29 $742.4K $75.00M 1 2020-06-08
Carisma Therapeutics Inc. (EBIO) Delisted 10%+ Owner 282,015 — — -$4.12M 1 2016-09-08

Recent Filings

6 filings
Insider activity across all companies, newest first. Form 4 rows are post-trade confirmations (buys, sells, grants, exercises). Notice (144) rows are pre-trade notices of intent to sell restricted or control stock under Rule 144 — they may not all execute. Compare adjacent dates to see which notices became actual sales.
Filed Symbol Action Net Shares Net $ Link
2024-12-13 — Notice (144) −216,590 -$49.8K EDGAR
2020-11-25 MCRB Other (J) −71,164,611 $0 EDGAR
2020-08-19 MRNA Other (J) −44,212,196 $0 EDGAR
2020-06-08 Kaleido Biosciences, Inc. (KLDO) Delisted Buy (P) +10,000,000 $75.00M EDGAR
2020-05-13 MRNA Other (J) −49,124,716 $0 EDGAR
2016-09-08 Carisma Therapeutics Inc. (EBIO) Delisted Sell (S) −906,479 -$4.12M EDGAR
Form 4 codes: P = open-market purchase · S = open-market sale · A = grant/award · M = option exercise · F = tax withholding at vest · G = bona-fide gift · D = disposition to issuer · J = other (see filing footnote). Only P / S codes carry directional signal.
Notice (144 / 144/A): Form 144 is a notice of intent to sell restricted/control stock under Rule 144, filed before the sale; 144/A is an amendment. Many notices are pre-scheduled under Rule 10b5-1 plans. A Form 4 with code S typically follows within a few days when the planned sale executes; missing follow-up Form 4s suggest the notice was cancelled or modified.