# EDGAR Filing Document

**Accession Number:** 0001746466
**File Stem:** 0001193125-26-124181
**Filing Date:** 2026-3
**Character Count:** 19233
**Document Hash:** 2d01bd07e14cdf4c9d6e909ae5831b80
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-124181.hdr.sgml**: 20260325

**ACCESSION NUMBER**: 0001193125-26-124181

**CONFORMED SUBMISSION TYPE**: S-8

**PUBLIC DOCUMENT COUNT**: 15

**FILED AS OF DATE**: 20260325

**DATE AS OF CHANGE**: 20260325

**EFFECTIVENESS DATE**: 20260325

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Equillium, Inc.
- **CENTRAL INDEX KEY:** 0001746466
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 821554746
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** S-8
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-294599
- **FILM NUMBER:** 26792833

**BUSINESS ADDRESS:**
- **STREET 1:** 2223 AVENIDA DE LA PLAYA
- **STREET 2:** SUITE 105
- **CITY:** LA JOLLA
- **STATE:** CA
- **ZIP:** 92037
- **BUSINESS PHONE:** (858) 412-5302

**MAIL ADDRESS:**
- **STREET 1:** 2223 AVENIDA DE LA PLAYA
- **STREET 2:** SUITE 105
- **CITY:** LA JOLLA
- **STATE:** CA
- **ZIP:** 92037

**As filed with the Securities and Exchange Commission on March 25, 2026** 

**Registration No. 333-** 

**UNITED STATES** 

**SECURITIES AND EXCHANGE COMMISSION** 

**Washington, D.C. 20549** 

**FORM S-8**

**REGISTRATION STATEMENT** 

***UNDER***

***THE SECURITIES ACT OF 1933***

## Equillium, Inc.
**(Exact name of registrant as specified in its charter)** 

---

| | |
|:---|:---|
| **Delaware** | **82-1554746** |
| **(State or other jurisdiction of**<br> **incorporation or organization)** | **(I.R.S. Employer**<br> **Identification No.)** |
| **2223 Avenida de la Playa, Suite 105**<br> **La Jolla, California** | **92037** |
| **(Address of Principal Executive Offices)** | **(Zip Code)** |

---

**2018 Equity Incentive Plan** 

**2018 Employee Stock Purchase Plan** 

**(Full titles of the plans)** 

**Bruce D. Steel** 

**Chief Executive Officer** 

**Equillium, Inc.** 

**2223 Avenida de la Playa, Suite 105** 

**La Jolla, California 92037** 

**(Name and Address of agent for service)** 

**(858) 240-1200**

**(Telephone number, including area code, of agent for service)** 

***With a copy to:***

**Thomas A. Coll** 

**Dylan S. Kornbluth** 

**Cooley LLP** 

**10265 Science Center Drive** 

**San Diego, California 92121** 

**(858) 550-6000**

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act:

---

| | | | |
|:---|:---|:---|:---|
| Large accelerated filer | ☐ | Accelerated filer | ☐ |
| Non-accelerated filer | ☒ | Smaller reporting company | ☒ |
|  |  | Emerging growth company | ☐ |

---

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

------

**REGISTRATION OF ADDITIONAL SECURITIES** 

**PURSUANT TO GENERAL INSTRUCTION E** 

This Registration Statement is being filed for the purpose of increasing the number of securities of the same class as other securities for which a Registration Statement of the Registrant on Form S-8 relating to the same employee benefit plans is effective.

The Registrant previously registered shares of its Common Stock for issuance under the Equillium, Inc. 2018 Equity Incentive Plan and the Equillium, Inc. 2018 Employee Stock Purchase Plan under Registration Statements on Form S-8 filed with the Securities and Exchange Commission on [October 16, 2018](http://www.sec.gov/Archives/edgar/data/0001746466/000119312518300276/d632051ds8.htm) (File No. 333-227859), [March 27, 2019](http://www.sec.gov/Archives/edgar/data/0001746466/000156459019009583/eq-s8.htm) (File No. 333-230536), as amended on [May 24, 2019](http://www.sec.gov/Archives/edgar/data/1746466/000156459019020466/eq-s8pos.htm), [March 26, 2020](http://www.sec.gov/Archives/edgar/data/1746466/000156459020013212/eq-s8.htm) (File No. 333-237407), [March 24, 2021](http://www.sec.gov/Archives/edgar/data/1746466/000156459021015107/eq-s8.htm) (File No. 333-254656), [March 23, 2022](http://www.sec.gov/Archives/edgar/data/1746466/000119312522082766/d300923ds8.htm) (File No. 333-263790), [January 6, 2023](http://www.sec.gov/Archives/edgar/data/1746466/000119312523003658/d448098ds8.htm) (File No. 333-269154), [March 25, 2024](http://www.sec.gov/Archives/edgar/data/1746466/000119312524076531/d786009ds8.htm) (File No. 333-278213) and [September 9, 2025](http://www.sec.gov/Archives/edgar/data/1746466/000119312525199243/d944623ds8.htm) (File No. 333-290140) (collectively, the "Prior Registration Statements"). Pursuant to General Instruction E to Form S-8, this Registration Statement hereby incorporates by reference the contents of the Prior Registration Statements.

**Item 8. Exhibits.** 

---

| | |
|:---|:---|
| **Exhibit<br>Number** | **Description** |
| &nbsp;&nbsp;&nbsp;&nbsp;4.1 | [Amended and Restated Certificate of Incorporation of the Registrant (incorporated by reference to Exhibit 3.1 of the Registrant's Current Report on Form 8-K filed on October 16, 2018).](http://www.sec.gov/Archives/edgar/data/1746466/000119312518300246/d634419dex31.htm) |
| &nbsp;&nbsp;&nbsp;&nbsp;4.2 | [Amended and Restated Bylaws of the Registrant (incorporated by reference to Exhibit 3.2 of the Registrant's Current Report on Form 8-K filed on October 16, 2018).](http://www.sec.gov/Archives/edgar/data/1746466/000119312518300246/d634419dex32.htm) |
| &nbsp;&nbsp;&nbsp;&nbsp;4.3 | [Form of Common Stock Certificate of the Registrant (incorporated by reference to Exhibit 4.1 of the Registrant's Registration Statement on Form S-1 (File No. 333-227387), as amended, originally filed on September 17, 2018).](http://www.sec.gov/Archives/edgar/data/1746466/000119312518290169/d582934dex41.htm) |
| &nbsp;&nbsp;&nbsp;&nbsp;5.1\* | [Opinion of Cooley LLP.](d25194dex51.htm) |
| 23.1\* | [Consent of Crowe LLP.](d25194dex231.htm) |
| 23.2\* | [Consent of KPMG LLP.](d25194dex232.htm) |
| 23.3\* | [Consent of Cooley LLP. Reference is made to Exhibit 5.1.](d25194dex51.htm) |
| 24.1\* | [Power of Attorney. Reference is made to the signature page hereto.](#tx25194_1) |
| 99.1 | [Equillium, Inc. 2018 Equity Incentive Plan, as amended, and Forms of Stock Option Grant Notice, Option Agreement and Notice of Exercise thereunder (incorporated by reference to Exhibit 99.1 of the Registrant's Registration Statement on Form S-8 (File No. 333-290140), filed on September 9, 2025).](http://www.sec.gov/Archives/edgar/data/1746466/000119312525199243/d944623dex991.htm) |
| 99.2 | [Equillium, Inc. 2018 Employee Stock Purchase Plan (incorporated by reference to Exhibit 99.3 of the Registrant's Registration Statement on Form S-8 (File No. 333-227859) filed on October 16, 2018).](http://www.sec.gov/Archives/edgar/data/1746466/000119312518300276/d632051dex993.htm) |
| 107\* | [Filing Fee Table.](d25194dexfilingfees.htm) |

---

\* Filed herewith.

------

**SIGNATURES** 

Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of La Jolla, State of California, on March 25, 2026.

---

| | |
|:---|:---|
| **EQUILLIUM, INC.** | **EQUILLIUM, INC.** |
| By: | /s/ Bruce D. Steel |
|  | Bruce D. Steel |
|  | Chief Executive Officer<br> (Principal Executive Officer and Principal Financial Officer) |

---

**POWER OF ATTORNEY** 

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below hereby constitutes and appoints Bruce D. Steel and Christine Zedelmayer, and each of them, as his or her true and lawful attorneys-in-fact and agents, with full power of substitution, for him or her in any and all capacities, to sign any and all amendments to this Registration Statement on Form S-8 (including post-effective amendments), and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully for all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or his substitute, may lawfully do or cause to be done by virtue hereof

Pursuant to the requirements of the Securities Act of 1933, this registration statement on Form S-8 has been signed by the following persons in the capacities and on the date indicated.

------

---

| | | |
|:---|:---|:---|
| **SIGNATURE** | **TITLE** | **DATE** |
| /s/ Bruce D. Steel<br> **Bruce D. Steel** | Chief Executive Officer and Director<br> *(Principal Executive Officer and Principal Financial Officer)* | March 25, 2026 |
| /s/ Penny Tom<br> **Penny Tom** | Senior Vice President, Finance<br> *(Principal Accounting Officer)* | March 25, 2026 |
| /s/ Daniel M. Bradbury<br> **Daniel M. Bradbury** | Chairman of the Board of Directors | March 25, 2026 |
| /s/ Peter Colabuono<br> **Peter Colabuono** | Director | March 25, 2026 |
| /s/ Martha J. Demski<br> **Martha J. Demski** | Director | March 25, 2026 |
| /s/ Charles McDermott<br> **Charles McDermott** | Director | March 25, 2026 |
| /s/ Mark Pruzanski, M.D.<br> **Mark Pruzanski, M.D**. | Director | March 25, 2026 |
| /s/ Barbara Troupin, M.D.<br> **Barbara Troupin, M.D**. | Director | March 25, 2026 |

---

## Exhibit 5.1

**Exhibit 5.1**![LOGO](g25194g0324135640764.jpg)

Thomas A. Coll

+1 858 550 6013

collta@cooley.com

March 25, 2026

Equillium, Inc.

2223 Avenida De La Playa, Suite 105

La Jolla, CA, 92037

Ladies and Gentlemen:

We have acted as counsel to Equillium, Inc., a Delaware corporation (the "***Company***"), in connection with the filing by the Company of a registration statement on Form S-8 (the "***Registration Statement***") with the Securities and Exchange Commission (the "***Commission***") covering the offering by the Company of up to 4,957,328 shares (the "***Shares***") of its common stock, par value $0.0001 per share ("***Common Stock***"), consisting of (i) 4,614,053 shares of Common Stock issuable pursuant to the Company's 2018 Equity Incentive Plan (the "***2018 Plan***"), (ii) 343,275 shares of Common Stock issuable pursuant to the Company's 2018 Employee Stock Purchase Plan (together with the 2018 Plan, the "***Plans***").

In connection with this opinion, we have examined and relied upon (a) the Registration Statement and the related prospectuses, (b) the Company's certificate of incorporation and bylaws, each as currently in effect, (c) the Plans and (d) such other records, documents, opinions, certificates, memoranda and instruments as in our judgment are necessary or appropriate to enable us to render the opinion expressed below. We have assumed the genuineness of all signatures, the authenticity of all documents submitted to us as originals, the conformity to originals of all documents submitted to us as copies, the accuracy, completeness and authenticity of certificates of public officials, and the due authorization, execution and delivery of all documents by all persons other than the Company. As to certain factual matters, we have relied upon a certificate of an officer of the Company and have not independently verified such matters.

Our opinion is expressed only with respect to the General Corporation Law of the State of Delaware. We express no opinion to the extent that any other laws are applicable to the subject matter hereof and express no opinion and provide no assurance as to compliance with any federal or state securities law, rule or regulation.

On the basis of the foregoing, and in reliance thereon, we are of the opinion that the Shares, when sold and issued in accordance with the Plans, the Registration Statement and the related prospectuses, will be validly issued, fully paid and nonassessable (except as to Shares issued pursuant to deferred payment arrangements, which will be fully paid and nonassessable when such deferred payments are made in full).

This opinion is limited to the matters expressly set forth in this letter, and no opinion has been or should be implied, or may be inferred, beyond the matters expressly stated. This opinion speaks only as to law and facts in effect or existing as of the date hereof, and we have no obligation or responsibility to update or supplement this opinion to reflect any facts or circumstances that may hereafter come to our attention or any changes in law that may hereafter occur.

Cooley LLP 10265 Science Center Drive San Diego, CA 92121-1117

t: +1 858 550 6000 f: +1 858 550-6420 cooley.com

------

![LOGO](g25194g0324135640764.jpg)

We consent to the filing of this opinion as an exhibit to the Registration Statement. In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act of 1933, as amended, or the rules and regulations of the Commission thereunder.

---

| | |
|:---|:---|
| Sincerely,<br>Cooley LLP | Sincerely,<br>Cooley LLP |
| By: | /s/ Thomas A. Coll |
|  | Thomas A. Coll |

---

Cooley LLP 10265 Science Center Drive San Diego, CA 92121-1117

t: +1 858 550 6000 f: +1 858 550-6420 cooley.com

## Exhibit 23.1

**Exhibit 23.1** 

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in this Registration Statement on Form S-8 of Equillium, Inc. of our report dated March 25, 2026 relating to the consolidated balance sheet of Equillium, Inc. as of December 31, 2025 and the consolidated statements of operations and comprehensive loss, stockholders' equity, and cash flows for the year ended December 31, 2025, appearing in the Annual Report on Form 10-K of Equillium, Inc. for the year ended December 31, 2025.

/s/ Crowe LLP

Costa Mesa, California

March 25, 2026

## Exhibit 23.2

**Exhibit 23.2** 

**Consent of Independent Registered Public Accounting Firm** 

We consent to the use of our report dated March 27, 2025, with respect to the consolidated financial statements of Equillium, Inc. and subsidiaries, incorporated herein by reference.

 /s/ KPMG LLP<br>

San Diego, California

March 25, 2026

## Ex-Filing

?xml version='1.0' encoding='ASCII'? EX-FILING FEES

---

| |
|:---|
| **Calculation of Filing Fee Tables**  |
| &nbsp;&nbsp;&nbsp;&nbsp;**S-8**  |
| &nbsp;&nbsp;&nbsp;&nbsp;**Equillium, Inc.**  |

---

---

| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Security Type**  | **Security Class Title**  | **Fee Calculation Rule**  | **Amount Registered**  | **Proposed Maximum Offering Price Per Unit**  | **Maximum Aggregate Offering Price**  | **Fee Rate**  | **Amount of Registration Fee**  |
| 1 | Equity | Common Stock, $0.0001 par value per share, Equillium, Inc. 2018 Equity Incentive Plan | Other | 4614053 | $2.15 | $9920213.95 | 0.0001381 | $1369.99 |
| 2 | Equity | Common Stock, $0.0001 par value per share, Equillium, Inc. 2018 Employee Stock Purchase Plan | Other | 343275 | $1.83 | $628193.25 | 0.0001381 | $86.76 |
| Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: |  | $10548407.20  |  | $1456.75  |
| Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  |  |  |  | $0.00  |
| Net Fee Due:  | Net Fee Due:  | Net Fee Due:  | Net Fee Due:  | Net Fee Due:  |  |  |  | $1456.75  |

---

 **Offering Note** <br>

<sup>1</sup> Pursuant to Rule 416(a) under the Securities Act of 1933, as amended (the "Securities Act"), this Registration Statement shall also cover any additional shares of the Registrant's common stock (the "Common Stock") that become issuable under the Equillium, Inc. 2018 Equity Incentive Plan (as amended, the "2018 Plan") by reason of any stock dividend, stock split, recapitalization or other similar transaction. The amount of shares registered represents 4,614,053 shares of Common Stock that were automatically added to the shares authorized for issuance under the 2018 Plan on January 1, 2026 pursuant to an "evergreen" provision contained in the 2018 Plan. Pursuant to such provision, on January 1 of each year through January 1, 2028, the number of shares authorized for issuance under the 2018 Plan is automatically increased by an amount equal to the lesser of: (a) 5% of the total number of shares of the Registrant's capital stock outstanding (including shares underlying pre-funded warrants) on December 31 of the preceding calendar year and (b) a number of shares of Common Stock that may be determined by the Registrant's board of directors that is less than the preceding clause (a). The proposed maximum offering price per share and maximum aggregate offering price are made pursuant to Rule 457(h)(1) and Rule 457(c) of the Securities Act solely for purposes of calculating the registration fee, and are based upon the average of the high and low prices of the Common Stock on March 19, 2026, as reported on The Nasdaq Capital Market (the "Average Price").

<sup>2</sup> Pursuant to Rule 416(a) under the Securities Act, this Registration Statement shall also cover any additional shares of Common Stock that become issuable under the Equillium, Inc. 2018 Employee Stock Purchase Plan (the "2018 ESPP") by reason of any stock dividend, stock split, recapitalization or other similar transaction. The amount of shares registered represents shares of Common Stock that were automatically added to the shares authorized for issuance under the 2018 ESPP on January 1, 2026 pursuant to an "evergreen" provision contained in the 2018 ESPP. Pursuant to such provision, on January 1 of each year through January 1, 2028, the number of shares authorized for issuance under the 2018 ESPP is automatically increased by a number equal to the lesser of: (a) 1% of the total number of shares of the Registrant's capital stock outstanding (including shares underlying pre-funded warrants) on December 31 of the preceding calendar year and (b) 343,275 shares; or a number of shares of Common Stock that may be determined by the Registrant's board of directors that is less than (a) and (b). The proposed maximum offering price per share and maximum aggregate offering price are made pursuant to Rule 457(h)(1) and Rule 457(c) of the Securities Act solely for purposes of calculating the registration fee, and are based upon the Average Price multiplied by 85%, which is the percentage of the price per share applicable to purchases under the 2018 ESPP.

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| |
|:---|
| |
| **Rule 457(p)** |
| Fee Offset Claims |
| Fee Offset Sources |

---