Vylor Takes Corteva’s S&P 500 Seat, Twilio Set To Replace Warner Bros. Discovery — Both Stocks Rise After-Hours

• Vylor replaced Corteva in the S&P 500 on Thursday, the day the separation between the two closed and regular-way trading under the ticker VYLR began on the New York Stock Exchange.
• Twilio will replace Warner Bros. Discovery in the S&P 500. 
• Corteva replaces Olin in the MidCap 400.

Shares of Vylor (VYLR) and Twilio (TWLO) rose in after-hours trading on Thursday after S&P Dow Jones Indices said both will be added to the S&P 500, a change that forces index funds to buy the stocks.

Vylor, the seed and genetics business Corteva (CTVA) spun off, was added immediately. Twilio, the cloud software company, joins before the market open on Tuesday. While VYLR edged up 3% after-hours, TWLO gained 1.2%.

A Spin-Off Takes Corteva’s Seat

Vylor replaced Corteva in the S&P 500 on Thursday, the day the separation closed and regular-way trading under the ticker VYLR began on the New York Stock Exchange. Corteva itself leaves the S&P 500 before the open on October 6 and drops into the S&P MidCap 400. S&P said the smaller post-spin company is a better fit for the mid-cap index.

Twilio Moves Up From The MidCap 400

Twilio will replace Warner Bros. Discovery (WBD) in the S&P 500 before the open on October 6, and will leave the MidCap 400 the same morning. Inclusion tends to lift a stock because funds that track the index have to own it. Twilio had been in the MidCap 400 since August 2025.

Warner Bros. Discovery is coming out because Paramount Skydance (PSKY) is buying it, in a deal S&P said is expected to close soon, pending final conditions. After the merger, Paramount Skydance will switch its main listing to the New York Stock Exchange.

Rest Of The Shuffle

The Corteva move pushes others down the index ladder. Corteva replaces Olin (OLN) in the MidCap 400. Olin then replaces Qorvo in the S&P SmallCap 600. Qorvo (QRVO) is being bought by Skyworks Solutions (SWKS), an S&P 500 company, in a deal also expected to close soon.

FormFactor (FORM) moves up from the SmallCap 600 to the MidCap 400, taking the seat Twilio leaves. Workiva (WK) replaces FormFactor in the SmallCap 600. All of those changes take effect before the open on Tuesday.

How Did TWLO, CTVA Retail Traders React?

On Stocktwits, retail sentiment around TWLO stayed in ‘bullish’ territory over the past 24 hours, while message volume remained ‘high.’

Meanwhile, sentiment for CTVA rose from ‘bearish’ to ‘extremely bullish,’ alongside retail chatter increasing from ‘normal’ to ‘extremely high’ levels.

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