# EDGAR Filing Document

**Accession Number:** 0001786205
**File Stem:** 0001104659-26-057932
**Filing Date:** 2026-5
**Character Count:** 2735
**Document Hash:** ccb0f713725cd4dea179954810b29485
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-26-057932.hdr.sgml**: 20260508

**ACCESSION NUMBER**: 0001104659-26-057932

**CONFORMED SUBMISSION TYPE**: 15-12G

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20260508

**DATE AS OF CHANGE**: 20260508

**EFFECTIVENESS DATE**: 20260508

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Arcellx, Inc.
- **CENTRAL INDEX KEY:** 0001786205
- **STANDARD INDUSTRIAL CLASSIFICATION:** BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 472855917
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 15-12G
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-41259
- **FILM NUMBER:** 26958478

**BUSINESS ADDRESS:**
- **STREET 1:** 800 BRIDGE PARKWAY
- **CITY:** REDWOOD CITY
- **STATE:** CA
- **ZIP:** 94065
- **BUSINESS PHONE:** 240-327-0603

**MAIL ADDRESS:**
- **STREET 1:** 800 BRIDGE PARKWAY
- **CITY:** REDWOOD CITY
- **STATE:** CA
- **ZIP:** 94065

**UNITED STATES** 

**SECURITIES AND EXCHANGE COMMISSION** 

**Washington, D.C. 20549** 

**FORM 15** 

**CERTIFICATION AND NOTICE OF TERMINATION OF REGISTRATION** 

**UNDER SECTION 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934** 

**OR SUSPENSION OF DUTY TO FILE REPORTS UNDER SECTIONS 13 AND 15(d)** 

**OF THE SECURITIES EXCHANGE ACT OF 1934.** 

**Commission File No. 001-41259**

**Arcellx, Inc.**

**(Exact name of registrant as specified in its charter)** 

**800 Bridge Parkway**

**Redwood City, California 94065**

**(240) 327-0630** 

**(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)**

**Common Stock, par value $0.001 per share**

**(Title of each class of securities covered by this Form)**

**None** 

**(Titles of all other classes of securities for which a duty to file reports under Section 13(a) or 15(d) remains)** 

Please place an X in the box(es) to designate the appropriate rule provision(s) relied upon to terminate or suspend the duty to file reports:

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| | |
|:---|:---|
| Rule 12g-4(a)(1) | ⌧ |
| Rule 12g-4(a)(2) | ◻ |
| Rule 12h-3(b)(1)(i) | ⌧ |
| Rule 12h-3(b)(1)(ii) | ◻ |
| Rule 15d-6 | ◻ |
| Rule 15d-22(b) | ◻ |

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Approximate number of holders of record as of the certification or notice date: One holder.

Pursuant to the requirements of the Securities Exchange Act of 1934, Arcellx, Inc. has caused this certification/notice to be signed on its behalf by the undersigned duly authorized person.

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| | | | |
|:---|:---|:---|:---|
|  |  | **Arcellx, Inc.** | **Arcellx, Inc.** |
| Date: | *May 8, 2026* | By: | /s/ Andrew D. Dickinson |
|  |  |  | Andrew D. Dickinson |
|  |  |  | President and Treasurer |

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