---
title: "Reddit Set to Join S&P 500 and Sun Communities to Join S&P MidCap 400 | AVB Stock News"
type: "News"
locale: "en"
url: "https://longbridge.com/en/news/295853997.md"
description: "S&P Dow Jones Indices announced that Reddit Inc. (RDDT) will replace AvalonBay Communities Inc. (AVB) in the S&P 500 effective August 18, 2026. This change follows Equity Residential's acquisition of AvalonBay, with the combined entity Vivmark Residential remaining in the index. Additionally, Sun Communities Inc. (SUI) will replace Webster Financial Corp. (WBS) in the S&P MidCap 400 effective August 20, 2026, due to Banco Santander's acquisition of Webster Financial."
datetime: "2026-08-13T14:12:00.000Z"
locales:
  - [zh-CN](https://longbridge.com/zh-CN/news/295853997.md)
  - [en](https://longbridge.com/en/news/295853997.md)
  - [zh-HK](https://longbridge.com/zh-HK/news/295853997.md)
generator: "portal-rs"
---

# Reddit Set to Join S&P 500 and Sun Communities to Join S&P MidCap 400 | AVB Stock News

, /PRNewswire/ -- S&P Dow Jones Indices will make the following changes to the S&P 500 and S&P MidCap 400:

-   Reddit Inc. (NYSE: RDDT) will replace AvalonBay Communities Inc. (NYSE: AVB) in the S&P 500 effective prior to the opening of trading on Tuesday, August 18. S&P 500 constituent Equity Residential (NYSE: EQR) is acquiring AvalonBay Communities in a deal expected to be completed soon, pending final conditions. Post merger, the combined company will be renamed Vivmark Residential (NYSE: VMRK) and will remain in the S&P 500.
-   Sun Communities Inc. (NYSE: SUI) will replace Webster Financial Corp. (NYSE: WBS) in the S&P MidCap 400 effective prior to the opening of trading on Thursday, August 20. Banco Santander S.A. (BMEX / NYSE: SAN) is acquiring Webster Financial in a deal expected to be completed soon pending final conditions.

Following is a summary of the changes that will take place prior to the open of trading on the effective date:

**Effective Date**

**Index Name** 

**Action**

**Company Name**

**Ticker**

**GICS Sector**

**August 18, 2026**

S&P 500

Addition

Reddit

RDDT

Communication Services

**August 18, 2026**

S&P 500

Deletion

AvalonBay Communities

AVB

Financials

**August 20, 2026**

S&P MidCap 400

Addition

Sun Communities

SUI

Real Estate

**August 20, 2026**

S&P MidCap 400

Deletion

Webster Financial

WBS

Financials

ABOUT S&P DOW JONES INDICES

S&P Dow Jones Indices is the largest global resource for essential index-based concepts, data and research, and home to iconic financial market indicators, such as the S&P 500® and the Dow Jones Industrial Average®. More assets are invested in products based on our indices than products based on indices from any other provider in the world. Since Charles Dow invented the first index in 1884, S&P DJI has been innovating and developing indices across the spectrum of asset classes helping to define the way investors measure and trade the markets.

S&P Dow Jones Indices is a division of S&P Global (NYSE: SPGI), which provides essential intelligence for individuals, companies, and governments to make decisions with confidence. For more information, visit www.spglobal.com/spdji/en/.

**FOR MORE INFORMATION:**

**S&P Dow Jones Indices**  
index\_services@spglobal.com 

**Media Inquiries**  
spdji.comms@spglobal.com 

SOURCE S&P Dow Jones Indices

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## Related News & Research

- [With Webster in hand, Santander says it's poised for growth](https://longbridge.com/en/news/296520178.md)
- [Reddit begins testing a new audio and video experience, similar to popular TikTok videos](https://longbridge.com/en/news/296137042.md)
- [Tacita Capital Inc Takes $1.74 Million Position in Sun Communities, Inc. $SUI](https://longbridge.com/en/news/296470043.md)
- [Meeder Asset Management Inc. Makes New $1.36 Million Investment in Sun Communities, Inc. $SUI](https://longbridge.com/en/news/296337000.md)
- [Santander completes Webster Financial acquisition, issues 329,846,438 new shares at EUR 10.79 each](https://longbridge.com/en/news/296445161.md)

---
> **Disclaimer: This article is for reference only and does not constitute any investment advice.**