# EDGAR Filing Document

**Accession Number:** 0001782303
**File Stem:** 0001193125-26-187010
**Filing Date:** 2026-4
**Character Count:** 1177
**Document Hash:** 1b6e55814c6c73e0f56982f801502bb0
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-187010.hdr.sgml**: 20260428

**ACCESSION NUMBER**: 0001193125-26-187010

**CONFORMED SUBMISSION TYPE**: ARS

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20251231

**FILED AS OF DATE**: 20260428

**DATE AS OF CHANGE**: 20260428

**EFFECTIVENESS DATE**: 20260428

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Boundless Bio, Inc.
- **CENTRAL INDEX KEY:** 0001782303
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 830751369
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** ARS
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-41989
- **FILM NUMBER:** 26907768

**BUSINESS ADDRESS:**
- **STREET 1:** 10955 ALEXANDRIA WAY
- **STREET 2:** SUITE 100
- **CITY:** SAN DIEGO
- **STATE:** CA
- **ZIP:** 92121
- **BUSINESS PHONE:** (858) 766-9912

**MAIL ADDRESS:**
- **STREET 1:** 10955 ALEXANDRIA WAY
- **STREET 2:** SUITE 100
- **CITY:** SAN DIEGO
- **STATE:** CA
- **ZIP:** 92121

### Attached PDF Documents

**Attachment 1:** `bold_ars_2026.pdf`

_No text found in this document._