Filer Snapshot

EcoR1 Capital, LLC

CIK 0001587114. SEC filing timeline plus parsed ownership intelligence from 13F, 13D/G, and Forms 3/4/5 where available.

Entity type

Company

Total filings

126

Latest filing

14 Aug 2026

Industry

n/a

Filing-backed research brief

Start with the SEC data that changes for this CIK

Latest signal: 13F-HR for Q2 2026. Each card links back to the PortfolioSavvy page where the filing evidence is closest.

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Largest parsed holding

ZYME

$600.45M reported value

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13D/G large stake

ANRO

13 Jul 2026 · 5.8% ownership

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Source: SEC Schedule 13D/G

SCHEDULE 13G/A filed on 14 Aug 2026 for CIK 0001587114.

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Notable people
Oleg Nodelman
Ownership signals CIK-linked ownership evidence from parsed SEC filings. 1 signal
Parsed SEC ownership signals

Parsed SEC ownership coverage

These bars compare filing-backed value available in each disclosure family. Read them as separate lenses, not as one combined ownership total.

13F portfolio$2.02B

Quarterly institutional holdings reported on Form 13F; not total AUM.

Forms 3/4/5 positions$1.17B

Reporting-owner positions with enough filing detail to estimate value.

Latest reported 13F value

13F
$2.02B

Reported market value from the latest parsed Form 13F information table; this is not total assets under management.

Source: SEC Form 13FScope: U.S.-listed equity holdings

Forms 3/4/5 position value

3/4/5
$1.17B

Estimated from parsed Forms 3/4/5 when filings include enough share and price data.

Source: Forms 3/4/5Confidence: Estimated when price data is available

Largest 13F holdings

13F
ZYME ANAB AKTS CGON ETON
+15 moreCRSP ORIC TRAX LKFT NGNE STOK FULC LEGN BBOT MBX ZBIO ATRA RLAY AURA ODTX

Largest symbols in the latest parsed Form 13F information table.

Freshness: Latest parsed 13F period

Largest linked holdings

Largest issuer positions linked to this CIK across parsed 13F, 13D/G, and Forms 3/4/5 records.

MRTX ZYME ANAB ITOS PRTA GRPH TNGX VYGR
+5 moreTCRX MRSN ATRA ADAP CRVS

Largest 13F holdings

Largest symbols in the latest parsed Form 13F information table.

ZYME ANAB AKTS CGON ETON CRSP ORIC TRAX
+12 moreLKFT NGNE STOK FULC LEGN BBOT MBX ZBIO ATRA RLAY AURA ODTX

Largest active 13D stakes

Active large-stake positions disclosed in parsed Schedule 13D filings.

ZYME GLPG PRTA ITOS Aktis Oncology, Inc.

Largest active 13G stakes

Passive or institutional large-stake positions disclosed in parsed Schedule 13G filings.

APLS ORIC XNCR ANRO QURE ITOS
+14 moreFULC IMNM MREO ETON NGNE KURA TECX VYGR TNGX ATRA AVIR ADAP HLVX MRSN
How to read these SEC ownership signals
  • Read each filing family separately: Form 13F, Schedules 13D/G, and Forms 3/4/5 answer different SEC disclosure questions and should not be blended into one ownership total.
  • Use 13F values for visible U.S.-listed equity portfolios, 13D/G rows for large beneficial-owner stakes, and Forms 3/4/5 rows for reporting-owner positions and transactions.
  • Open the linked research path when you need the filing, CIK, issuer, CUSIP, date, or source trail behind a value.
At a glance Names, identifiers, and filing context for this profile. 1 identity field
Business address
357 Tehama Street #3, San Francisco, CA, 94103
EDGAR profile Static EDGAR fields kept behind disclosure so the main profile stays readable. 2 profile fields available
Incorporated in
DE
Fiscal year end
31 December

Filer intelligence

What SEC filings say about EcoR1 Capital, LLC

A compact read of parsed XML filings. 13F, 13D/G, and Forms 3/4/5 are shown separately because they answer different ownership questions.

Open 13F portfolio Save filer

Quick read

  • Latest parsed 13F shows $2.02B across 31 reported holdings for Q2 2026.
  • Largest parsed 13F holding: ZYME at $600.45M.
  • 5 recent 13D/G stake rows found; top row is ANRO at 5.8% ownership.
  • Forms 3/4/5 show insider context for MRTX worth $436.57M.

SEC source mix

Counts show available parsed rows, not one combined ownership total.

XML parsed
13F portfolio 31 rows

Quarterly institutional portfolio holdings.

Open
13D/G stakes 5 rows

Beneficial ownership and large-stake disclosures.

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Forms 3/4/5 5 rows

Officer, director, and 10% owner holdings or transactions.

Open

Top parsed 13F holdings

Visual share of the latest parsed 13F portfolio. Values are reported market value, not a recommendation.

Q2 2026 - 14 Aug 2026

Top 5 concentration

73%

Share of latest parsed 13F value represented by the visible holdings below.

Top 5 reported value

$1.47B

Compared with $2.02B total 13F value.

Top 5 net change

+$27.87M

Position-value change inside the visible top holdings only.

13F concentration map

A simple visual split of the latest parsed 13F portfolio.

Largest add: TRAX · Largest trim: JAZZ

ZYME ANAB AKTS CGON ETON Other holdings

ZYME

29.8%

Zymeworks Inc

$600.45M

ANAB

26.4%

Anaptysbio Inc

$531.91M

AKTS

7.7%

Aktis Oncology Inc

$155.49M

CGON

5.3%

Cg Oncology Inc

$106.17M

ETON

3.9%

Eton Pharmaceuticals Inc

$78.62M

13D/G large-stake context

ANRO

13 Jul 2026 · Comon Stock

5.8%
Issuer page 13D/G history

MREO

30 Jun 2026 · Ordinary Shares

0.6%
Issuer page 13D/G history

FULC

17 Jun 2026 · Common Stock

9%
Issuer page 13D/G history

Eloxx Pharmaceuticals, Inc.

09 Jun 2026 · Comon Stock

9.9%
Issuer page 13D/G history

Forms 3/4/5 insider context

MRTX

18 Dec 2023 · 10% owner

$436.57M
Issuer page Owner page

ZYME

26 Jun 2025 · 10% owner

$341.95M
Issuer page Owner page

ANAB

30 Dec 2024 · 10% owner

$102.05M
Issuer page Owner page

ITOS

14 May 2025 · 10% owner

$85.51M
Issuer page Owner page

Latest update

What changed recently for EcoR1 Capital, LLC

New filing available

Latest 13F period: Q2 2026. Open the source-backed page to inspect the fresh filing or facts context.

Update date

14 Aug 2026

Page type

Filer profile

Latest period

Q2 2026

Institutional portfolio context was refreshed from a 13F filing filed on 14 Aug 2026.

Open filer profile Browse recent public updates

Benchmark Context

Benchmark context for this company

EcoR1 Capital, LLC has a source-backed company facts view where you can compare the latest reported metrics with its own recent history and with peer rankings for the same metric.

Compared with

Start on the facts page for period-to-period context, then open a metric ranking when you want to compare the same reported fact across other SEC-reporting companies.

Why this is notable

Latest 13F period: Q2 2026. That gives you a fresh baseline before you compare this company with peers.

  • Peer comparisons stay conservative: same metric, compatible units, latest valid company row only.
  • Open the facts page first if you want the cleanest path to verification.

Benchmark context is only shown where the app has enough comparable SEC-backed data to keep the interpretation honest.

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SEC filing record

CIK 0001587114 filing coverage

Start with this filing record, then use the linked ownership pages when parsed 13F, 13D/G, Forms 3/4/5, or facts data exists for this CIK.

SEC filings
126
First seen
17 Feb 2015
Latest filing
14 Aug 2026
Entity
Company

Observed form types

13F-HR 13F-HR/A 3 4 SCHEDULE 13D SCHEDULE 13D/A SCHEDULE 13G SCHEDULE 13G/A

CIK-linked evidence first

EcoR1 Capital, LLC SEC filings EcoR1 Capital, LLC 13F portfolio EcoR1 Capital, LLC 13D/G history EcoR1 Capital, LLC owner filings Open SEC filing index

Latest Filings

Showing the latest 12 of 126 SEC filings for EcoR1 Capital, LLC.

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SCHEDULE 13G/A

SCHEDULE 13G/A filing

Filing date
14 Aug 2026
Reporting date
Not listed
SEC evidence
Open document Open filing
Next action
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13F-HR

13F-HR filing

Filing date
14 Aug 2026
Reporting date
30 Jun 2026
SEC evidence
Open document Open filing
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SCHEDULE 13G

SCHEDULE 13G filing

Filing date
20 Jul 2026
Reporting date
Not listed
SEC evidence
Open document Open filing
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SCHEDULE 13G

SCHEDULE 13G filing

Filing date
25 Jun 2026
Reporting date
Not listed
SEC evidence
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SCHEDULE 13G

SCHEDULE 13G filing

Filing date
25 Jun 2026
Reporting date
Not listed
SEC evidence
Open document Open filing
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SCHEDULE 13G

SCHEDULE 13G filing

Filing date
16 Jun 2026
Reporting date
Not listed
SEC evidence
Open document Open filing
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13F-HR

13F-HR filing

Filing date
15 May 2026
Reporting date
31 Mar 2026
SEC evidence
Open document Open filing
Next action
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SCHEDULE 13G/A

SCHEDULE 13G/A filing

Filing date
15 May 2026
Reporting date
Not listed
SEC evidence
Open document Open filing
Next action
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SCHEDULE 13G/A

SCHEDULE 13G/A filing

Filing date
15 May 2026
Reporting date
Not listed
SEC evidence
Open document Open filing
Next action
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SCHEDULE 13G/A

SCHEDULE 13G/A filing

Filing date
15 May 2026
Reporting date
Not listed
SEC evidence
Open document Open filing
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SCHEDULE 13G/A

SCHEDULE 13G/A filing

Filing date
15 May 2026
Reporting date
Not listed
SEC evidence
Open document Open filing
Next action
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SCHEDULE 13G/A

SCHEDULE 13G/A filing

Filing date
07 May 2026
Reporting date
Not listed
SEC evidence
Open document Open filing
Next action
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