# EDGAR Filing Document

**Accession Number:** 0001962918
**File Stem:** 0001104659-25-057733
**Filing Date:** 2025-6
**Character Count:** 2621
**Document Hash:** 708a72bac7cc50c12df815109f4451cb
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-25-057733.hdr.sgml**: 20250609

**ACCESSION NUMBER**: 0001104659-25-057733

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

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20250609

**DATE AS OF CHANGE**: 20250609

**EFFECTIVENESS DATE**: 20250609

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** ACELYRIN, Inc.
- **CENTRAL INDEX KEY:** 0001962918
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 852406735
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 15-12G
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-41696
- **FILM NUMBER:** 251033512

**BUSINESS ADDRESS:**
- **STREET 1:** 4149 LIBERTY CANYON RD.
- **CITY:** AGOURA HILLS
- **STATE:** CA
- **ZIP:** 91301
- **BUSINESS PHONE:** 805-456-4393

**MAIL ADDRESS:**
- **STREET 1:** 4149 LIBERTY CANYON RD.
- **CITY:** AGOURA HILLS
- **STATE:** CA
- **ZIP:** 91301

**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 Number 001-41696**

**ACELYRIN, INC.**

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

**4149 Liberty Canyon Road**

**Agoura Hills, California**

**(805) 456-4393**

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

**Common Stock, par value $0.00001 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) | x |
| 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: 17

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

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| | | |
|:---|:---|:---|
| Date: June 9, 2025 | By: | /s/ Sara Klein |
|  | Name: | Sara Klein |
|  | Title: | President and Secretary |

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