Twilio S&P 500 Warner Bros Discovery is the headline index story of the week: cloud-communications company Twilio (TWLO) will join the S&P 500 before the market opens on Tuesday, October 6, replacing Warner Bros. Discovery (WBD), which is leaving the benchmark as its $81 billion merger with Paramount Skydance (PSKY) is expected to close the same day, according to MarketWatch.
S&P Dow Jones Indices announced the changes late Thursday, triggering a run-up in the newly added stocks. Shares of Twilio rose 1.2% in after-hours trading on Thursday following the announcement, MarketWatch reported, and the stock climbed about 1.5% ahead of Friday’s opening bell, according to Barron’s. Stocks added to a major index typically rally because the passive funds that track those benchmarks are required to buy shares to match their composition.
Paramount Skydance’s $81B Warner Bros. Discovery Deal Paves the Way for Twilio’s S&P 500 Entry
After nearly a year of twists and turns, Warner Bros. Discovery is set to complete its $81 billion merger with Paramount Skydance, with both companies saying the deal is expected to close on Oct. 6, Barron’s reported. Once the transaction is done, WBD will cease to trade as an independent public company, forcing its removal from both the S&P 500 and the Nasdaq 100.
The merged company will be called Skydance and will trade under the ticker SKYD, replacing the current PSKY ticker, per Barchart. Warner Bros. Discovery shareholders will receive about $31 for each share of WBD stock they own as part of the transaction.
Twilio is moving up from the S&P MidCap 400 to take Warner Bros. Discovery’s place in the large-cap index, with chip-testing company FormFactor (FORM) set to fill Twilio’s old spot in the midcap benchmark, Barchart reported.
Twilio S&P 500 Inclusion Caps a Breakout Year for the Warner Bros. Discovery Replacement
Twilio, valued at roughly $46 billion, sells the programmable communications tools — voice, chat, email and messaging APIs — that companies use to talk to their customers, according to MarketWatch. The San Francisco company has spent the past year recasting itself as an artificial-intelligence play, arguing that the rise of AI agents will drive a surge in automated calls, texts and customer-service interactions that run across its platform.
“AI agents have the ability to drive significantly higher communications flows, unlocking incremental demand,” TD Cowen analyst Derrick Wood wrote in a note to clients, as quoted by MarketWatch. He added that when people hand tasks off to agents, “more calls and texts can be made as a person’s attention & time are no longer constraining factors.”
The pitch has worked. Twilio’s stock has more than tripled off its yearly low near $99 to trade around $305, a gain of more than 200%, according to Parameter.io, putting it among the best-performing large-cap tech names of 2026. Multiple Wall Street firms have raised price targets or ratings on the stock, citing the AI-agent opportunity.
Moderna Replaces Warner Bros. Discovery in the Nasdaq 100
Warner Bros. Discovery’s exit from the Nasdaq 100 opened a second high-profile slot. Nasdaq announced late Thursday that drug maker Moderna (MRNA) will replace WBD in the Nasdaq 100 before the market opens on Friday, Oct. 9, Barron’s reported. Moderna shares advanced 1.6% ahead of Friday’s open.
Moderna’s elevation follows a stellar run: the stock was up 541% for the year through Thursday’s close, according to Barron’s. Its shares more than doubled in a single session in August after Moderna and Merck’s investigational cancer vaccine, intismeran autogene, showed promising results in a Phase 3 trial.
Corteva Spins Off Vylor in a Second S&P 500 Swap
The Twilio–WBD change is not the only index shuffle driven by corporate deal-making this week. MarketWatch reported that Vylor (VYLR), the seed-and-genetics business spun off by crop-protection company Corteva (CTVA), has been added to the S&P 500 following the completion of that spinoff. Corteva, itself a 2019 spinoff from DowDuPont, was moved down to the S&P MidCap 400 given its new, smaller size.
Why Index Inclusion Matters for Twilio Stock
Joining the S&P 500 matters well beyond prestige. Trillions of dollars sit in index funds and ETFs that track the benchmark, and each of those funds must buy Twilio shares when it enters the index to keep their holdings aligned. That mechanical demand is the main reason newly added stocks tend to jump — and why Twilio’s after-hours and premarket gains followed the announcement.
For investors, the effective message is simple: as of Tuesday’s opening bell, the company sitting in Warner Bros. Discovery’s old seat in the S&P 500 is a cloud-software firm that has rebranded itself as one of the biggest beneficiaries of the AI-agent boom.
FAQ
When does Twilio join the S&P 500?
Twilio’s addition to the S&P 500 is effective before the open of trading on Tuesday, October 6, 2026, replacing Warner Bros. Discovery, according to S&P Dow Jones Indices.
Why is Warner Bros. Discovery leaving the S&P 500?
WBD is being removed because its $81 billion merger with Paramount Skydance is expected to close on Oct. 6. After the deal, WBD will no longer trade as an independent public company, so it is being dropped from both the S&P 500 and the Nasdaq 100.
What happens to WBD shareholders in the merger?
Warner Bros. Discovery shareholders are expected to receive about $31 for each share of WBD stock they own, and the merged company will be called Skydance, trading under the ticker SKYD.
Who else is joining the major indexes?
Moderna will replace Warner Bros. Discovery in the Nasdaq 100 before the open on Oct. 9, and Vylor — Corteva’s seed-and-genetics spinoff — has joined the S&P 500, with Corteva moving down to the S&P MidCap 400.
Sources: MarketWatch, Barron’s, Barchart.
Leave a Reply
You must be logged in to post a comment.