Monashee Investment Management LLC — 13F Holdings & Portfolio
CIK 1627608 · latest 13F-HR filed 2026-08-13
Monashee Investment Management LLC manages $59.6M in 13F-reported U.S. long-equity assets across 23 reported positions as of its 2026-06-30 13F-HR filing. Its largest disclosed positions are GOOGM (8.54%), GOOGN (8.44%), SLDB (8.38%). Quarter over quarter (versus its 2026-03-31 filing) the fund opened 21 new positions and exited 43; 0 existing positions rose in reported value and 2 fell.
AUM is the long-equity portion reported on Form 13F-HR. Excludes short positions, cash, foreign holdings, and non-13F assets. For informational purposes only — not investment advice.
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AUM
$59.6M
Long-equity book
Holdings
23
Distinct positions
Period
2026-06-30
Filed 2026-08-13
Q/Q Activity
+21 / −43 / ↑0 / ↓2
vs 2026-03-31
Portfolio charts
Latest quarter's book, what changed, and how the portfolio has evolved across filings.
Portfolio map
Q2 26GOOGM8.5% · newGOOGN8.4% · newSLDB8.4% · -65%DLR7.5% · newSYRE7.5% · newADT6.5% · -14%TNGX5.2% · newCELC4.8% · newSMCIP4.4% · newLEGN4.1% · newGOOGL3.6% · newGOOG3.6% · newQURE3.5% · newINIO3.2% · newAKR3.0% · newPTRN2.7% · newPCTTW2.6% · newMLTX2.5% · newWHK2.4% · newTSHA2.3% · newIMA1.9% · newNUVB1.8% · newKARD1.7% · new
Box size = position value; colour = change in share count vs the prior quarter (green added, red trimmed, blue new). Rows split across managers or share classes are combined. Click a box for the stock.
Sector mix
% of 13F valueSectors from each company's SIC code; funds and ETFs grouped separately.
Biggest buys and sells
Q1 26 → Q2 26Estimated from the change in shares held × the quarter-end price, so price moves alone don't count as buying. New and exited positions are included.
13F assets and positions
4 quartersTotal reported 13F value (bars) and number of positions (line) each quarter. Value changes include market moves.
Top positions over time
reported valueThe eight largest current positions, valued at each quarter end.
Concentration
top 10 = 65.4%Cumulative share of the portfolio held in the largest N positions.
Firm Profile & Key People
As of the firm’s regulatory filing dated Feb 27, 2026.
Assets Under Management
$1.86B
Discretionary
$1.86B
Employees
13
Accounts
12
| Name | Title / Status | Ownership | Type |
|---|---|---|---|
| MONASHEE HOLDINGS LLC Control | MANAGING MEMBER since Dec 2017 | 75% or more | Domestic Entity |
| MULLER, JEFFRY, THOMAS Control | CHIEF OPERATING OFFICER, CHIEF COMPLIANCE OFFICER since May 2014 | Less than 5% | Individual |
| SCHLISMAN, ADAM, DAVID Control | CHIEF ADMINISTRATION OFFICER, CHIEF FINANCIAL OFFICER since Jan 2025 | Less than 5% | Individual |
| WYNN, THOMAS, JOSEPH Control | MANAGING PARTNER since Dec 2011 | Less than 5% | Individual |
| FISKE ROAD LIMITED PARTNERSHIP Control Indirect owner via MONASHEE HOLDINGS LLC | MEMBER since Oct 2019 | 25–50% | Domestic Entity |
| MONASHEE LLC Control Indirect owner via FISKE ROAD LIMITED PARTNERSHIP | GENERAL PARTNER since Oct 2019 | General partner, trustee or manager | Domestic Entity |
| WYNN, THOMAS, JOSEPH Control Indirect owner via FISKE ROAD LIMITED PARTNERSHIP | LIMITED PARTNER since Oct 2019 | 75% or more | Individual |
| JEFFERIES FINANCIAL GROUP INC. Indirect owner via LEUCADIA ASSET MANAGEMENT HOLDINGS LLC | MEMBER since Dec 2021 | 75% or more | Foreign Entity |
| LEUCADIA ASSET MANAGEMENT HOLDINGS LLC Indirect owner via MONASHEE HOLDINGS LLC | MEMBER since Dec 2021 | 25–50% | Domestic Entity |
Ownership & leadership changes · 11 filings with changes since Apr 4, 2012
From the firm’s regulatory filings, newest first. Dates are filing dates: a filing that no longer lists someone does not say when they left.
Feb 26, 2025 filing
- No longer listedBuckley, Daniel, James · CHIEF FINANCIAL OFFICER · Less than 5% · listed since Mar 2020
- No longer listedJEFFERIES FINANCIAL GROUP LLC · MEMBER · 75% or more · indirect via LEUCADIA ASSET MANAGEMENT HOLDINGS LLC · listed since Dec 2021
- AddedJEFFERIES FINANCIAL GROUP INC. · MEMBER · 75% or more · indirect via LEUCADIA ASSET MANAGEMENT HOLDINGS LLC
- AddedSCHLISMAN, ADAM, DAVID · CHIEF ADMINISTRATION OFFICER, CHIEF FINANCIAL OFFICER · Less than 5% · control person
- ChangedMULLER, JEFFRY, THOMAS · title CHIEF COMPLIANCE OFFICER, HEAD OF OPERATIONS → CHIEF OPERATING OFFICER, CHIEF COMPLIANCE OFFICER
Dec 21, 2023 filing
- No longer listedCOUGHLAN, GERALD, EMAN · MANAGING PARTNER · Less than 5% · control person · listed since Dec 2011
- No longer listedCOUGHLAN, GERALD, EMAN · LIMITED PARTNER · 50–75% · indirect via FISKE ROAD LIMITED PARTNERSHIP · control person · listed since Oct 2019
- ChangedJEFFERIES FINANCIAL GROUP LLC · indirect via LEUCADIA ASSET MANAGEMENT HOLDINGS LLC: no longer a control person
- ChangedLEUCADIA ASSET MANAGEMENT HOLDINGS LLC · indirect via MONASHEE HOLDINGS LLC: no longer a control person
- ChangedWYNN, THOMAS, JOSEPH · indirect via FISKE ROAD LIMITED PARTNERSHIP: ownership 50–75% → 75% or more
Feb 28, 2023 filing
- No longer listedJEFFERIES GROUP LLC · MEMBER · 75% or more · indirect via LEUCADIA ASSET MANAGEMENT HOLDINGS LLC · control person · listed since Dec 2021
- AddedJEFFERIES FINANCIAL GROUP LLC · MEMBER · 75% or more · indirect via LEUCADIA ASSET MANAGEMENT HOLDINGS LLC · control person
Dec 22, 2021 filing
- No longer listedJEFFERIES FINANCIAL GROUP INC. · MEMBER · 75% or more · indirect via LAM HOLDING LLC · control person · listed since Jun 2013
- No longer listedLAM HOLDING LLC · MEMBER · 25–50% · indirect via MONASHEE HOLDINGS LLC · control person · listed since Oct 2019
- AddedJEFFERIES GROUP LLC · MEMBER · 75% or more · indirect via LEUCADIA ASSET MANAGEMENT HOLDINGS LLC · control person
- AddedLEUCADIA ASSET MANAGEMENT HOLDINGS LLC · MEMBER · 25–50% · indirect via MONASHEE HOLDINGS LLC · control person
Mar 26, 2020 filing
- No longer listedCANAVAN, JOSEPH, WILLIAM · CHIEF FINANCIAL OFFICER · Less than 5% · listed since May 2018
- AddedBuckley, Daniel, James · CHIEF FINANCIAL OFFICER · Less than 5%
Nov 1, 2019 filing
- No longer listedCOUGHLAN, GERALD, EMAN · MEMBER · 25–50% · indirect via MONASHEE HOLDINGS LLC · control person · listed since Dec 2011
- No longer listedWYNN, THOMAS, JOSEPH · MEMBER · 25–50% · indirect via MONASHEE HOLDINGS LLC · control person · listed since Dec 2011
- AddedCOUGHLAN, GERALD, EMAN · LIMITED PARTNER · 50–75% · indirect via FISKE ROAD LIMITED PARTNERSHIP · control person
- AddedFISKE ROAD LIMITED PARTNERSHIP · MEMBER · 25–50% · indirect via MONASHEE HOLDINGS LLC · control person
- AddedJEFFERIES FINANCIAL GROUP INC. · MEMBER · 75% or more · indirect via LAM HOLDING LLC · control person
- AddedLAM HOLDING LLC · MEMBER · 25–50% · indirect via MONASHEE HOLDINGS LLC · control person
- AddedMONASHEE LLC · GENERAL PARTNER · General partner, trustee or manager · indirect via FISKE ROAD LIMITED PARTNERSHIP · control person
- AddedWYNN, THOMAS, JOSEPH · LIMITED PARTNER · 50–75% · indirect via FISKE ROAD LIMITED PARTNERSHIP · control person
- ChangedCOUGHLAN, GERALD, EMAN · title CHIEF INVESTMENT OFFICER → MANAGING PARTNER
- ChangedWYNN, THOMAS, JOSEPH · title CHIEF OPERATING OFFICER → MANAGING PARTNER
Mar 26, 2019 filing
- AddedCANAVAN, JOSEPH, WILLIAM · CHIEF FINANCIAL OFFICER · Less than 5%
Jan 30, 2018 filing
- No longer listedCOUGHLAN, GERALD, EMAN · MEMBER · 25–50% · indirect via GID HEDGE FUND HOLDINGS II LLC · control person · listed since Dec 2011
- No longer listedGID HEDGE FUND HOLDINGS II LLC · MANAGING MEMBER · 75% or more · control person · listed since Dec 2011
- No longer listedREAL ESTATE EQUITIES LLC · MANAGING MEMBER · 75% or more · indirect via WINDSOR ADVISERS SECURITIES II LLC · control person · listed since Sep 2011
- No longer listedWINDSOR ADVISERS SECURITIES II LLC · MEMBER · 50–75% · indirect via GID HEDGE FUND HOLDINGS II LLC · control person · listed since Dec 2011
- No longer listedWYNN, THOMAS, JOSEPH · MEMBER · 25–50% · indirect via GID HEDGE FUND HOLDINGS II LLC · control person · listed since Dec 2011
- AddedCOUGHLAN, GERALD, EMAN · MEMBER · 25–50% · indirect via MONASHEE HOLDINGS LLC · control person
- AddedMONASHEE HOLDINGS LLC · MANAGING MEMBER · 75% or more · control person
- AddedWYNN, THOMAS, JOSEPH · MEMBER · 25–50% · indirect via MONASHEE HOLDINGS LLC · control person
Mar 30, 2016 filing
- No longer listedGID EXECUTIVE INCENTIVE LLC · MEMBER · 25–50% · indirect via WINDSOR ADVISERS SECURITIES II LLC · control person · listed since Sep 2011
Jun 11, 2014 filing
- No longer listedLASALA, JOSEPH · CHIEF ADMINISTRATIVE OFFICER · Less than 5% · control person · listed since Nov 2012
- AddedMULLER, JEFFRY, THOMAS · CHIEF COMPLIANCE OFFICER, HEAD OF OPERATIONS · Less than 5% · control person
- ChangedWYNN, THOMAS, JOSEPH · title CHIEF COMPLIANCE OFFICER, CHIEF OPERATING OFFICER → CHIEF OPERATING OFFICER
Older changes (2 more filings)
Apr 1, 2013 filing
- No longer listedNOBLE, ALEXANDER, TYLER · CHIEF ADMINISTRATIVE OFFICER · Less than 5% · control person · listed since Dec 2011
- AddedLASALA, JOSEPH · CHIEF ADMINISTRATIVE OFFICER · Less than 5% · control person
Apr 4, 2012 filing (earliest on record)
- ListedCOUGHLAN, GERALD, EMAN · CHIEF INVESTMENT OFFICER · Less than 5% · control person
- ListedCOUGHLAN, GERALD, EMAN · MEMBER · 25–50% · indirect via GID HEDGE FUND HOLDINGS II LLC · control person
- ListedGID EXECUTIVE INCENTIVE LLC · MEMBER · 25–50% · indirect via WINDSOR ADVISERS SECURITIES II LLC · control person
- ListedGID HEDGE FUND HOLDINGS II LLC · MANAGING MEMBER · 75% or more · control person
- ListedNOBLE, ALEXANDER, TYLER · CHIEF ADMINISTRATIVE OFFICER · Less than 5% · control person
- ListedREAL ESTATE EQUITIES LLC · MANAGING MEMBER · 75% or more · indirect via WINDSOR ADVISERS SECURITIES II LLC · control person
- ListedWINDSOR ADVISERS SECURITIES II LLC · MEMBER · 50–75% · indirect via GID HEDGE FUND HOLDINGS II LLC · control person
- ListedWYNN, THOMAS, JOSEPH · CHIEF COMPLIANCE OFFICER, CHIEF OPERATING OFFICER · Less than 5% · control person
- ListedWYNN, THOMAS, JOSEPH · MEMBER · 25–50% · indirect via GID HEDGE FUND HOLDINGS II LLC · control person
Quarter-over-quarter changes
Changes in reported position value vs the prior 13F, so price moves count too, not just shares bought or sold.
New Positions
- ALPHABET INC$5.1M
- ALPHABET INC$5.0M
- DIGITAL RLTY TR INC$4.5M
- SPYRE THERAPEUTICS INC$4.4M
- TANGO THERAPEUTICS INC$3.1M
Exited Positions
- TERNS PHARMACEUTICALS INC$15.8M
- NEXTERA ENERGY INC$15.2M
- MEDLINE INC$13.3M
- NRG ENERGY INC$12.4M
- FORGENT POWER SOLUTIONS INC$10.2M
Monashee Investment Management LLC Holdings (2026-06-30)
Rows tagged Call or Put are options positions, not stock. Per SEC Form 13F-HR, Value shows the notional value of the underlying (shares covered × underlying price), not the option premium. Shares is the number of underlying shares covered (divide by 100 for contract count).
| # | Issuer | Symbol | CUSIP | Value | Weight | Shares | Type |
|---|---|---|---|---|---|---|---|
| 1 | ALPHABET INC | GOOGM | 02079K404 | $5.1M | 8.54% | 100,000 | SH |
| 2 | ALPHABET INC | GOOGN | 02079K602 | $5.0M | 8.44% | 100,000 | SH |
| 3 | SOLID BIOSCIENCES INC | SLDB | 83422E204 | $5.0M | 8.38% | 500,000 | SH |
| 4 | DIGITAL RLTY TR INC | DLR | 253868103 | $4.5M | 7.53% | 25,000 | SH |
| 5 | SPYRE THERAPEUTICS INC | SYRE | 00773J202 | $4.4M | 7.45% | 50,000 | SH |
| 6 | ADT INC DEL | ADT | 00090Q103 | $3.9M | 6.55% | 600,000 | SH |
| 7 | TANGO THERAPEUTICS INC | TNGX | 87583X109 | $3.1M | 5.25% | 100,000 | SH |
| 8 | CELCUITY INC | CELC | 15102KAB6 | $2.8M | 4.76% | 2,500,000 | PRN |
| 9 | SUPER MICRO COMPUTER INC | SMCIP | 86800U500 | $2.6M | 4.36% | 50,000 | SH |
| 10 | LEGEND BIOTECH CORP | LEGN | 52490G102 | $2.5M | 4.14% | 85,385 | SH |
| 11 | ALPHABET INC | GOOGL | 02079K305 | $2.1M | 3.60% | 6,000 | SH |
| 12 | ALPHABET INC | GOOG | 02079K107 | $2.1M | 3.56% | 6,000 | SH |
| 13 | UNIQURE NV | QURE | N90064101 | $2.1M | 3.48% | 45,000 | SH |
| 14 | INNIO NV | INIO | N52A8C105 | $1.9M | 3.16% | 47,650 | SH |
| 15 | ACADIA RLTY TR | AKR | 004239109 | $1.8M | 3.00% | 85,385 | SH |
| 16 | PATTERN GROUP INC | PTRN | 70339W104 | $1.6M | 2.71% | 64,039 | SH |
| 17 | PURECYCLE TECHNOLOGIES INC | PCTTW | 74623VAD5 | $1.5M | 2.58% | 1,500,000 | PRN |
| 18 | MOONLAKE IMMUNOTHERAPEUTICS | MLTX | 61559X104 | $1.5M | 2.45% | 75,000 | SH |
| 19 | WHITEHAWK MINERALS CORP | WHK | 96524T101 | $1.4M | 2.39% | 51,232 | SH |
| 20 | TAYSHA GENE THERAPIES INC | TSHA | 877619106 | $1.4M | 2.29% | 200,000 | SH |
| 21 | IMAGENEBIO INC | IMA | 45175G207 | $1.1M | 1.90% | 192,344 | SH |
| 22 | NUVATION BIO INC | NUVB | 67080NAA9 | $1.1M | 1.77% | 1,000,000 | PRN |
| 23 | KARDIGAN INC | KARD | 485925101 | $1.0M | 1.71% | 42,693 | SH |
Filing History
| Period | Filed | AUM | Holdings | Accession |
|---|---|---|---|---|
| 2026-06-30 | 2026-08-13 | $59.6M | 23 | 0001172661-26-003357 |
| 2026-03-31 | 2026-05-13 | $183.8M | 45 | 0001172661-26-001803 |
| 2025-12-31 | 2026-02-12 | $177.5M | 40 | 0001172661-26-000650 |
| 2025-09-30 | 2025-11-12 | $200.5M | 61 | 0001172661-25-004710 |
Filer Information
Address
75 PARK PLAZA4TH FLOOR
BOSTON, MA 02116
Phone
(617) 671-0048
Filing Manager
Monashee Investment Management LLC
Boston, MA
Signatory
Jeff Muller
COO/CCO