Sandisk Set to Join S&P 500; Upwork, First Interstate BancSystem, PTC Therapeutics to Join S&P SmallCap 600

Rhea-AI Summary

Gildan (NYSE: GIL) and several companies will move between S&P indices effective late November–early December 2025. Sandisk (SNDK) is being added to the S&P 500 on November 28, 2025, with PTC Therapeutics (PTCT) joining the S&P SmallCap 600 the same day. Upwork (UPWK) and First Interstate BancSystem (FIBK) also join the SmallCap 600 on November 28 and December 2, 2025, respectively; Interpublic, Premier and Hanesbrands will be removed.

AI-generated analysis. Not financial advice.

Positive

• Sandisk added to S&P 500 on November 28, 2025
• PTC Therapeutics added to S&P SmallCap 600 on November 28, 2025
• Upwork added to S&P SmallCap 600 on November 28, 2025
• First Interstate BancSystem added to S&P SmallCap 600 on December 2, 2025

Negative

• Interpublic deleted from S&P 500 on November 28, 2025
• Hanesbrands deleted from S&P SmallCap 600 on December 2, 2025
• Premier deleted from S&P SmallCap 600 on November 28, 2025

Key Figures

Index change date: November 28, 2025 Index change date: December 2, 2025 Premier deal close: November 25, 2025 +5 more

8 metrics

Index change date November 28, 2025 Effective date for PTCT addition to S&P SmallCap 600

Index change date December 2, 2025 Effective date for FIBK addition to S&P SmallCap 600

Premier deal close November 25, 2025 Expected completion date of Patient Square Capital acquisition of Premier

Hanesbrands deal close December 1, 2025 Expected completion date of Gildan Activewear acquisition of Hanesbrands

Current price $70.42 PTCT price prior to index inclusion effective date

Daily move 2.52% PTCT 24h price change ahead of index change

52-week range $35.95–$87.50 PTCT 52-week low and high before index change

Market cap $5,685,796,204 PTCT market capitalization pre-index inclusion

Market Reality Check

Price: $73.69 Vol: Volume 661,529 is at 0.67...

low vol

$73.69 Last Close

Volume Volume 661,529 is at 0.67x the 20-day average of 989,453, indicating subdued trading activity pre-index change. low

Technical PTCT at $70.42 is trading above its 200-day MA of $65.04 and sits 19.52% below its 52-week high of $87.50 while up 95.88% from its 52-week low of $35.95.

Peers on Argus

PTCT gained 2.52% with mixed peer action: RNA (+5.06%), CRSP (+7.32%), KRYS (+3....

PTCT gained 2.52% with mixed peer action: RNA (+5.06%), CRSP (+7.32%), KRYS (+3.20%), TGTX (+0.27%), and MRUS (-7.08%). With no peers in the momentum scanner and divergent moves, today’s action appears more stock-specific than a broad biotech rotation.

Historical Context

5 past events · Latest: Mar 25 (Positive)

Pattern 5 events

Date	Event	Sentiment	Move	Catalyst
Mar 25	Board appointment	Positive	+3.4%	Veteran biotech banker Jessica Chutter added to board, supporting strategic depth.
Mar 13	Inducement grants	Neutral	+2.5%	Inducement stock options and RSUs granted to 18 new employees under Nasdaq rules.
Feb 23	Investor conferences	Neutral	-0.2%	Announced participation in three March investor conferences with webcast access.
Feb 19	Earnings update	Positive	+1.1%	Reported strong 2025 revenues, cash balance, Sephience launch, and royalty transaction.
Feb 18	Sector report	Positive	+1.4%	Third-party report highlighting growth outlook for phenylketonuria market including peers.

Pattern Detected

Recent news — board additions, financial results, and corporate updates — has usually been followed by modestly positive price reactions, with only one small divergence on a neutral conference update.

Recent Company History

Over the last few months, PTC Therapeutics has reported several constructive developments. Earnings on Feb 19, 2026 highlighted $1.731B in 2025 revenue and $1.945B year-end cash, followed by generally positive price reactions. Corporate updates such as investor conference participation and inducement equity grants led to small moves. A governance milestone came on Mar 25, 2026 with Jessica Chutter’s board appointment, again with a positive reaction. Today’s index-related inclusion news fits into a pattern of incremental, market-supported corporate progress.

Market Pulse Summary

This announcement highlights PTCT’s upcoming addition to the S&P SmallCap 600 as Sandisk moves to th...

Analysis

This announcement highlights PTCT’s upcoming addition to the S&P SmallCap 600 as Sandisk moves to the S&P 500 and other names exit due to M&A. Index changes can affect trading dynamics by altering the shareholder base and benchmark-driven ownership, but they do not alter fundamentals directly. In context of prior earnings strength and governance updates, investors may watch how ownership, liquidity, and subsequent corporate developments evolve after the effective dates on November 28, 2025 and December 2, 2025.

Key Terms

s&p 500, s&p smallcap 600, gics sector

3 terms

s&p 500 financial

"Sandisk Corp. (NASD: SNDK) will replace The Interpublic Group of Companies Inc. (NYSE: IPG) in the S&P 500"

The S&P 500 is a broad stock market index that tracks the performance of 500 large U.S. companies, weighted so bigger firms have a larger impact. Investors use it like a thermometer or benchmark to judge how the overall U.S. stock market or a portfolio is doing; movements in the index influence investor sentiment, fund performance, and many passive investment products that aim to match its returns.

s&p smallcap 600 financial

"S&P SmallCap 600 constituent Sandisk Corp. (NASD: SNDK) will replace The Interpublic Group"

A stock market index made up of 600 small-cap U.S. companies chosen to represent the performance of smaller publicly traded firms. It matters to investors because it acts like a temperature gauge for the small-company segment of the market, serving as a benchmark for fund managers, a basis for index funds and ETFs, and a way to compare returns and risk when building a diversified portfolio.

gics sector financial

"Effective Date | Index Name | Action | Company Name | Ticker | GICS Sector"

GICS sector is one of the major industry groupings from the Global Industry Classification Standard, a system that sorts companies into consistent categories (like Technology or Health Care) based on the primary business they do. Investors use these sectors like folders in a filing cabinet to compare companies, build diversified portfolios, and track how whole parts of the market are performing rather than focusing on single stocks.

AI-generated analysis. Not financial advice.

NEW YORK, Nov. 24, 2025 /PRNewswire/ -- S&P Dow Jones Indices will make the following changes to the S&P 500, S&P SmallCap 600: 

• S&P SmallCap 600 constituent Sandisk Corp. (NASD: SNDK) will replace The Interpublic Group of Companies Inc. (NYSE: IPG) in the S&P 500, and PTC Therapeutics Inc. (NASD: PTCT) will replace Sandisk in the S&P SmallCap 600 effective prior to the opening of trading on Friday, November 28. S&P 500 constituent Omnicom Group Inc. (NYSE: OMC) is acquiring The Interpublic Group of Companies in a deal expected to close soon, pending final conditions.
  
  
• Upwork Inc. (NASD: UPWK) will replace Premier Inc. (NASD: PINC) in the S&P SmallCap 600 effective prior to the open of trading on Friday, November 28. Patient Square Capital is acquiring Premier in a deal expected to be completed November 25, pending final closing conditions.
  
  
• First Interstate BancSystem Inc. (NASD: FIBK) will replace Hanesbrands Inc. (NYSE: HBI) in the S&P SmallCap 600 effective prior to the opening of trading on Tuesday, December 2. Gildan Activewear (TMX/NYSE: GIL) is acquiring Hanesbrands in a deal expected to be completed December 1, pending final closing 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
November 28, 2025	S&P 500	Addition	Sandisk	SNDK	Information Technology
November 28, 2025	S&P 500	Deletion	Interpublic Group	IPG	Communication Services
November 28, 2025	S&P SmallCap 600	Addition	Upwork	UPWK	Industrials
November 28, 2025	S&P SmallCap 600	Addition	PTC Therapeutics	PTCT	Health Care
November 28, 2025	S&P SmallCap 600	Deletion	Sandisk	SNDK	Information Technology
November 28, 2025	S&P SmallCap 600	Deletion	Premier	PINC	Health Care
December 02, 2025	S&P SmallCap 600	Addition	First Interstate BancSystem	FIBK	Financials
December 02, 2025	S&P SmallCap 600	Deletion	Hanesbrands	HBI	Consumer Discretionary

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
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View original content:https://www.prnewswire.com/news-releases/sandisk-set-to-join-sp-500-upwork-first-interstate-bancsystem-ptc-therapeutics-to-join-sp-smallcap-600-302625036.html

SOURCE S&P Dow Jones Indices

FAQ

When will Sandisk (SNDK) join the S&P 500 and what is the effective date?

Sandisk (SNDK) will join the S&P 500 effective prior to the open on November 28, 2025. According to S&P Dow Jones Indices, the change is scheduled to occur before trading begins on that date.

Which companies are being added to the S&P SmallCap 600 on November 28, 2025?

Upwork (UPWK) and PTC Therapeutics (PTCT) will be added to the S&P SmallCap 600 on November 28, 2025. According to S&P Dow Jones Indices, both additions occur effective prior to the open of trading.

Why is Interpublic (IPG) being removed from the S&P 500 on November 28, 2025?

Interpublic (IPG) is being removed because it is being acquired by Omnicom, with the deal expected to close soon. According to S&P Dow Jones Indices, the pending acquisition triggers the index deletion.

When will First Interstate BancSystem (FIBK) join the S&P SmallCap 600 and why?

First Interstate BancSystem (FIBK) will join the S&P SmallCap 600 effective prior to the open on December 2, 2025. According to S&P Dow Jones Indices, the addition follows index rebalancing tied to recent corporate changes.

What happens to Hanesbrands (HBI) in the S&P SmallCap 600 after Gildan's acquisition?

Hanesbrands (HBI) will be deleted from the S&P SmallCap 600 effective December 2, 2025. According to S&P Dow Jones Indices, Gildan's expected acquisition and related corporate changes lead to the removal.