# EDGAR Filing Document

**Accession Number:** 0001285819
**File Stem:** 0001437749-26-004950
**Filing Date:** 2026-2
**Character Count:** 7175
**Document Hash:** af9ccffc3c088078afc4889939bed60b
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001437749-26-004950.hdr.sgml**: 20260220

**ACCESSION NUMBER**: 0001437749-26-004950

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20260218

**FILED AS OF DATE**: 20260220

**DATE AS OF CHANGE**: 20260220

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Demopulos Gregory A MD
- **CENTRAL INDEX KEY:** 0001472160

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-34475
- **FILM NUMBER:** 26661927

**MAIL ADDRESS:**
- **STREET 1:** 201 ELLIOTT AVENUE WEST
- **CITY:** SEATTLE
- **STATE:** WA
- **ZIP:** 98119
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** OMEROS CORP
- **CENTRAL INDEX KEY:** 0001285819
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 911663741
- **STATE OF INCORPORATION:** WA
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 201 ELLIOTT AVENUE WEST
- **CITY:** SEATTLE
- **STATE:** WA
- **ZIP:** 98119
- **BUSINESS PHONE:** 206-676-5000

**MAIL ADDRESS:**
- **STREET 1:** 201 ELLIOTT AVENUE WEST
- **CITY:** SEATTLE
- **STATE:** WA
- **ZIP:** 98119

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

[ ] Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Demopulos Gregory A MD<br><sub>(Last) (First) (Middle)</sub><br>201 ELLIOTT AVENUE WEST<br><sub>(Street)</sub><br>SEATTLE, WA 98119<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-02-18 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director [ ] 10% Owner<br>[X] Officer (give title below) [ ] Other (specify below)<br>_Chairman, CEO & President_ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>OMEROS CORP [ OMER ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| Common stock | 2026-02-18 |  | M |  | 400000 | A | $10.27 | 1826986 | D |  |
| Common stock | 2026-02-18 |  | F |  | 357678<sup>(1)</sup> | D | $11.93 | 1469308 | D |  |
| Common stock |  |  |  |  |  |  |  | 300000<sup>(2)</sup> | I | By trust<sup>(3)</sup> |
| Common stock |  |  |  |  |  |  |  | 300000<sup>(2)</sup> | I | By trust<sup>(4)</sup> |
| Common stock |  |  |  |  |  |  |  | 123945<sup>(2)</sup> | I | By spouse |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| Stock option (right to buy) | $10.27 | 2026-02-18 |  | M |  |  | 400000 | <sup>(5)</sup> | 2026-02-19 | Common stock | 400000 | $0 | 0 | D |  |

---

### Footnotes:

(1) Represents shares withheld by Omeros Corporation ("Omeros") in connection with net share settlement to satisfy the exercise price and tax liability associated with the reporting person's exercise of stock options. The number of shares withheld was determined based on the closing price of Omeros' common stock on February 17, 2026. The transaction did not involve any open-market sale of securities, and all 357,678 withheld shares remained in the Omeros treasury.

(2) The reporting person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, if any, and nothing in this report shall be deemed an admission that the reporting person is the beneficial owner of such securities under Section 16 of the Securities Exchange Act of 1934 or for any other purpose.

(3) Shares held in the [Demopulos Child #1] Gift Trust, an irrevocable trust established for the benefit of a minor child of the reporting person.

(4) Shares held in the [Demopulos Child #2] Gift Trust, an irrevocable trust established for the benefit of a minor child of the reporting person.

(5) This option vested and became exercisable over 48 equal monthly installments, with a vesting commencement date of April 1, 2015.

**Signature:** /s/ Peter B. Cancelmo, Attorney-in-Fact  
**Date:** 2026-02-20

### Remarks:

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**