# EDGAR Filing Document

**Accession Number:** 0001096903
**File Stem:** 0001193125-26-274068
**Filing Date:** 2026-6
**Character Count:** 2091
**Document Hash:** ad0e566b4ae091308c80a49f38944479
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-274068.hdr.sgml**: 20260617

**ACCESSION NUMBER**: 0001193125-26-274068

**CONFORMED SUBMISSION TYPE**: 497

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20260617

**DATE AS OF CHANGE**: 20260617

**EFFECTIVENESS DATE**: 20260617

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** COHEN & STEERS INSTITUTIONAL REALTY SHARES INC
- **CENTRAL INDEX KEY:** 0001096903

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** MD
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 497
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-89183
- **FILM NUMBER:** 261098169

**BUSINESS ADDRESS:**
- **STREET 1:** 1166 AVENUE OF THE AMERICAS
- **STREET 2:** 30TH FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10036
- **BUSINESS PHONE:** 2128323232

**MAIL ADDRESS:**
- **STREET 1:** 1166 AVENUE OF THE AMERICAS
- **STREET 2:** 30TH FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10036

## Series and Classes Contracts Data

### Cohen & Steers Institutional Realty Shares (Series ID: S000011976)

---

|  |  |  |
|:---|:---|:---|
| Class Name                                 | Ticker Symbol | Class ID   |
| Cohen & Steers Institutional Realty Shares | CSRIX         | C000032692 |

---

## Series and Classes Contracts Data

### Cohen & Steers Institutional Realty Shares (Series ID: S000011976)

| Class ID   | Class Name                                 | Ticker Symbol   |
|:---|:---|:---|
| C000032692 | Cohen & Steers Institutional Realty Shares | CSRIX           |

**COHEN & STEERS INSTITUTIONAL REALTY SHARES, INC.** 

Supplement dated June 17, 2026 to Prospectus dated May 1, 2026

*On June 16, 2026, the Board of Directors approved a change to the fiscal year end for Cohen & Steers Institutional Realty Shares, Inc. (the "Fund") from December 31 to October 31. Effective October 1, 2026, references to the Fund's prior fiscal year end are hereby deleted and replaced with the new fiscal year end of October 31.* 

THE REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK.

CSIRSPRO – 6.26