# EDGAR Filing Document

**Accession Number:** 0001627608
**File Stem:** 0001172661-25-004710
**Filing Date:** 2025-11
**Character Count:** 9944
**Document Hash:** 1668e624476cd54a6077d987326afa7d
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001172661-25-004710.hdr.sgml**: 20251112

**ACCESSION NUMBER**: 0001172661-25-004710

**CONFORMED SUBMISSION TYPE**: 13F-HR

**PUBLIC DOCUMENT COUNT**: 2

**CONFORMED PERIOD OF REPORT**: 20250930

**FILED AS OF DATE**: 20251112

**DATE AS OF CHANGE**: 20251112

**EFFECTIVENESS DATE**: 20251112

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Monashee Investment Management LLC
- **CENTRAL INDEX KEY:** 0001627608

**ORGANIZATION NAME:**
- **EIN:** 453324374
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1130

**FILING VALUES:**
- **FORM TYPE:** 13F-HR
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 028-16854
- **FILM NUMBER:** 251470812

**BUSINESS ADDRESS:**
- **STREET 1:** 75 PARK PLAZA
- **STREET 2:** 4TH FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02116
- **BUSINESS PHONE:** 6176710048

**MAIL ADDRESS:**
- **STREET 1:** 75 PARK PLAZA
- **STREET 2:** 4TH FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02116

### FORM 13F COVER PAGE

**Report for the Calendar Year or Quarter Ended:** 09-30-2025

**Check here if Amendment** [ ] **Amendment Number:** 

**This Amendment (Check only one.):** [ ] is a restatement.

[ ] adds new holdings entries.

**Institutional Investment Manager Filing this Report:**

**Name:** Monashee Investment Management LLC<br>**Address:** 75 Park Plaza<br>4th Floor<br>Boston, MA 02116

**Form 13F File Number:** 028-16854

**CRD Number (if applicable):** 000163148

**SEC File Number (if applicable):** 801-79936

The institutional investment manager filing this report and the person by whom it is signed hereby represent that the person signing the report is authorized to submit it, that all information contained herein is true, correct and complete, and that it is understood that all required items, statements, schedules, lists, and tables, are considered integral parts of this form.

**Person Signing this Report on Behalf of Reporting Manager:**

**Name:** Jeff Muller<br>**Title:** COO/CCO<br>**Phone:** 617-671-0048

**Signature, Place, and Date of Signing:**

/s/ Jeff Muller  Boston, MA  11-12-2025<br>[Signature]  [City, State]  [Date]

**Report Type (Check only one.):**

[x] **13F HOLDINGS REPORT.** (Check here if all holdings of this reporting manager are reported in this report.)

[ ] **13F NOTICE.** (Check here if no holdings are reported in this report, and all holdings are reported by other reporting manager(s).)

[ ] **13F COMBINATION REPORT.** (Check here if a portion of the holdings for this reporting manager are reported in this report and a portion are reported by other reporting manager(s).)

### Form 13F Summary Page

**Report Summary:**

**Number of Other Included Managers:** 0

**Form 13F Information Table Entry Total:** 61

**Form 13F Information Table Value Total:** $200538185

      (round to nearest dollar)

**List of Other Included Managers:**

Provide a numbered list of the name(s) and Form 13F file number(s) of all institutional investment managers with respect to which this report is filed, other than the manager filing this report.

[If there are no entries in this list, state “NONE” and omit the column headings and list entries.]

**NONE**

### FORM 13F INFORMATION TABLE

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| NAME OF ISSUER | TITLE OF CLASS | CUSIP | FIGI | VALUE (x$1000) | SHRS OR PRN AMT | SH/PRN | PUT/CALL | INVESTMENT DISCRETION | OTHER MANAGER | VOTING AUTHORITY | VOTING AUTHORITY | VOTING AUTHORITY |
| NAME OF ISSUER | TITLE OF CLASS | CUSIP | FIGI | VALUE (x$1000) | SHRS OR PRN AMT | SH/PRN | PUT/CALL | INVESTMENT DISCRETION | OTHER MANAGER | SOLE | SHARED | NONE |
| ADT INC DEL | COM | 00090Q103 |  | 3919500 | 450000 | SH |  | SOLE |  | 450000 | 0 | 0 |
| AIRO GROUP HLDGS INC | COM | 009422106 |  | 1920000 | 100000 | SH |  | SOLE |  | 100000 | 0 | 0 |
| AMBIQ MICRO INC | COMMON STOCK | 023193105 |  | 5984000 | 200000 | SH |  | SOLE |  | 200000 | 0 | 0 |
| AMYLYX PHARMACEUTICALS INC | COM | 03237H101 |  | 407604 | 30000 | SH |  | SOLE |  | 30000 | 0 | 0 |
| AVIDITY BIOSCIENCES INC | COM | 05370A108 |  | 2178500 | 50000 | SH |  | SOLE |  | 50000 | 0 | 0 |
| BIODESIX INC | COM | 09075X207 |  | 754970 | 99996 | SH |  | SOLE |  | 99996 | 0 | 0 |
| BIT DIGITAL INC | SHS | G1144A105 |  | 4500000 | 1500000 | SH |  | SOLE |  | 1500000 | 0 | 0 |
| BLACK ROCK COFFEE BAR INC | CL A | 092244102 |  | 2386000 | 100000 | SH |  | SOLE |  | 100000 | 0 | 0 |
| BRIDGEBIO PHARMA INC | COM | 10806X102 |  | 10388000 | 200000 | SH |  | SOLE |  | 200000 | 0 | 0 |
| BRUKER CORP | 6.375 PREF SER A | 116794207 |  | 3805200 | 14000 | SH |  | SOLE |  | 14000 | 0 | 0 |
| BULLISH | ORD SHS | G16910120 |  | 3180500 | 50000 | SH |  | SOLE |  | 50000 | 0 | 0 |
| CANTOR EQUITY PARTNERS II IN | CL A ORD SHS | G1827P106 |  | 1344975 | 127971 | SH |  | SOLE |  | 127971 | 0 | 0 |
| CANTOR EQUITY PARTNERS III I | SHS CL A | G1828A108 |  | 2064000 | 200000 | SH |  | SOLE |  | 200000 | 0 | 0 |
| CANTOR EQUITY PARTNERS IV IN | SHS CL A | G1828E100 |  | 1018500 | 100000 | SH |  | SOLE |  | 100000 | 0 | 0 |
| CARETRUST REIT INC | COM | 14174T107 |  | 2080800 | 60000 | SH |  | SOLE |  | 60000 | 0 | 0 |
| CARLSMED INC | COM | 14280C105 |  | 535600 | 40000 | SH |  | SOLE |  | 40000 | 0 | 0 |
| CHIME FINL INC | COM SHS CL A | 16935C109 |  | 2218700 | 110000 | SH |  | SOLE |  | 110000 | 0 | 0 |
| CIPHER MINING INC | COM | 17253J106 |  | 1888500 | 150000 | SH |  | SOLE |  | 150000 | 0 | 0 |
| CIRCLE INTERNET GROUP INC | COM CL A | 172573107 |  | 2651600 | 20000 | SH |  | SOLE |  | 20000 | 0 | 0 |
| COMPASS THERAPEUTICS INC | COM | 20454B104 |  | 4375000 | 1250000 | SH |  | SOLE |  | 1250000 | 0 | 0 |
| COREBRIDGE FINL INC | COM | 21871X109 |  | 6410000 | 200000 | SH |  | SOLE |  | 200000 | 0 | 0 |
| COREWEAVE INC | COM CL A | 21873S108 |  | 2737000 | 20000 | SH |  | SOLE |  | 20000 | 0 | 0 |
| CYTOKINETICS INC | COM NEW | 23282W605 |  | 5496000 | 100000 | SH |  | SOLE |  | 100000 | 0 | 0 |
| ENERGY FUELS INC | COM NEW | 292671708 |  | 2302500 | 150000 | SH |  | SOLE |  | 150000 | 0 | 0 |
| EQV VENTURES AC CORP. II | UNIT 06/30/2032 | G3106Q110 |  | 2252250 | 225000 | SH |  | SOLE |  | 225000 | 0 | 0 |
| EVOLENT HEALTH INC | DEBT 4.500% 8/1 | 30050BAJ0 |  | 2011120 | 2000000 | PRN |  | SOLE |  | 2000000 | 0 | 0 |
| FIGMA INC | CLASS A COM STK | 316841105 |  | 2593500 | 50000 | SH |  | SOLE |  | 50000 | 0 | 0 |
| FIGURE TECHNOLOGY SOLUTIO | COM CL A | 349381103 |  | 7274000 | 200000 | SH |  | SOLE |  | 200000 | 0 | 0 |
| FORWARD INDS INC N Y | COM NEW | 349862409 |  | 10366231 | 405406 | SH |  | SOLE |  | 405406 | 0 | 0 |
| FOX CORP | CL B COM | 35137L204 |  | 4010300 | 70000 | SH |  | SOLE |  | 70000 | 0 | 0 |
| FUTURECREST ACQUISITION CORP | UNIT 99/99/9999 | G3730U123 |  | 106000 | 10000 | SH |  | SOLE |  | 10000 | 0 | 0 |
| GEMINI SPACE STA INC | CL A COM | 36866J105 |  | 1437600 | 60000 | SH |  | SOLE |  | 60000 | 0 | 0 |
| GOSSAMER BIO INC | NOTE 5.000% 6/0 | 38341PAA0 |  | 714160 | 1000000 | PRN |  | SOLE |  | 1000000 | 0 | 0 |
| HINGE HEALTH INC | CL A | 433313103 |  | 2454000 | 50000 | SH |  | SOLE |  | 50000 | 0 | 0 |
| HOLLEY INC | COM | 43538H103 |  | 1099000 | 350000 | SH |  | SOLE |  | 350000 | 0 | 0 |
| IMMUNEERING CORP | CLASS A COM | 45254E107 |  | 2100000 | 300000 | SH |  | SOLE |  | 300000 | 0 | 0 |
| KLARNA GROUP PLC | SHS | G5279N105 |  | 3665000 | 100000 | SH |  | SOLE |  | 100000 | 0 | 0 |
| KLAVIYO INC | COM SER A | 49845K101 |  | 1107600 | 40000 | SH |  | SOLE |  | 40000 | 0 | 0 |
| LATAM AIRLINES GROUP SA | SPONSORED ADR | 51817R205 |  | 6108750 | 135000 | SH |  | SOLE |  | 135000 | 0 | 0 |
| LB PHARMACEUTICALS INC | COM SHS | 50180M108 |  | 631600 | 40000 | SH |  | SOLE |  | 40000 | 0 | 0 |
| LEGENCE CORP | CL A | 52476L109 |  | 4621500 | 150000 | SH |  | SOLE |  | 150000 | 0 | 0 |
| MCGRAW HILL INC | COM | 580907103 |  | 753000 | 60000 | SH |  | SOLE |  | 60000 | 0 | 0 |
| MIAMI INTL HLDGS INC | COM | 59356Q108 |  | 6039000 | 150000 | SH |  | SOLE |  | 150000 | 0 | 0 |
| MIRION TECHNOLOGIES INC | COM CL A | 60471A101 |  | 2326000 | 100000 | SH |  | SOLE |  | 100000 | 0 | 0 |
| NEBIUS GROUP N.V. | SHS CLASS A | N97284108 |  | 4490800 | 40000 | SH |  | SOLE |  | 40000 | 0 | 0 |
| NETSKOPE INC | CL A | 64119N608 |  | 6819000 | 300000 | SH |  | SOLE |  | 300000 | 0 | 0 |
| NEWS CORP NEW | CL B | 65249B208 |  | 4146000 | 120000 | SH |  | SOLE |  | 120000 | 0 | 0 |
| NIQ GLOBAL INTELLIGENCE PLC | ORDINARY SHARES | G63755105 |  | 942000 | 60000 | SH |  | SOLE |  | 60000 | 0 | 0 |
| PATTERN GROUP INC | COM SER A | 70339W104 |  | 2055000 | 150000 | SH |  | SOLE |  | 150000 | 0 | 0 |
| PEPGEN INC | COM | 713317105 |  | 1386000 | 300000 | SH |  | SOLE |  | 300000 | 0 | 0 |
| SHOULDER INNOVATIONS INC | COMMON STOCK | 82537J108 |  | 502000 | 40000 | SH |  | SOLE |  | 40000 | 0 | 0 |
| SLIDE INS HLDGS INC | COM | 831349105 |  | 2762375 | 175000 | SH |  | SOLE |  | 175000 | 0 | 0 |
| SMITHFIELD FOODS INC | COM | 832248207 |  | 4226400 | 180000 | SH |  | SOLE |  | 180000 | 0 | 0 |
| STRUCTURE THERAPEUTICS INC | SPONSORED ADS | 86366E106 |  | 5600000 | 200000 | SH |  | SOLE |  | 200000 | 0 | 0 |
| STUBHUB HLDGS INC | CL A | 86384P109 |  | 3368000 | 200000 | SH |  | SOLE |  | 200000 | 0 | 0 |
| TRANSOCEAN LTD | REGISTERED SHS | H8817H100 |  | 936000 | 300000 | SH |  | SOLE |  | 300000 | 0 | 0 |
| UNIQURE NV | SHS | N90064101 |  | 2334800 | 40000 | SH |  | SOLE |  | 40000 | 0 | 0 |
| VIA TRANSN INC | COM CL A | 92556W104 |  | 3365600 | 70000 | SH |  | SOLE |  | 70000 | 0 | 0 |
| WATERBRIDGE INFRASTRUCTURE L | CL A SHS REPSTG | 940923105 |  | 6052800 | 240000 | SH |  | SOLE |  | 240000 | 0 | 0 |
| WAYSTAR HLDG CORP | COM | 946784105 |  | 5688000 | 150000 | SH |  | SOLE |  | 150000 | 0 | 0 |
| WHITEFIBER INC | SHS | G96115103 |  | 9645350 | 355000 | SH |  | SOLE |  | 355000 | 0 | 0 |

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