Odds On: S&P 500 inclusion expectations reset after surprise pick

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The S&P Dow Jones Indices selection committee surprised investors overnight when it selected Datadog (DDOG) to replace Juniper Networks (JNPR) – being acquired by HP Enterprise (HPE) – in the pre-eminent S&P 500 index effective July 9. After all, Datadog’s market capitalization of below $50B was well shy of the front-runner Robinhood’s (HOOD) over $80B. Speculation was also arising that the committee would opt for a company in the Financial sector, where the index was under-represented, making Robinhood or a company such as Ares Management (ARES) – market cap nearly $60B – a more apt selection, though perhaps with Coinbase (COIN) being the last name added to the index, the S&P was resigned to “slow its roll” on the rapidly expanding DeFi industry encroaching on its membership.

With quarterly rebalancing in the index the norm, will Robinhood be redeemed with the golden ticket to enter the coveted S&P 500 when the committee presumably meets again in September or before the end of 2025? 

THE BET: Heading into last night’s selection, the Kalshi Events Market pegged Robinhood’s chances of entering the S&P 500 at 63%, followed by a 50% probability of entry for Ares Management. Flutter Entertainment (FLUT) – a same-industry future darkhorse candidate as a potential replacement for a company like Caesars (CZR), whose current market cap of $6.2B is well below S&P 500 threshold of entry of $20.5B – was a distant third at 12%. This morning, the post-selection reset has Robinhood’s odds of S&P 500 entry at 12%, followed by Flutter’s 5% and Ares Management’s 4% before January 1 of 2026. The betting parameters are even more asymmetric – the platform currently allows a bettor to wager $6 to win $100 if Robinhood is tapped for index entry. Conversely, a bettor can click “NO” for any of these names, though a $100 win on this event contract would require a $95-$96 outlay.

PROGRESS ON S&P 500 COMPONENT M&A:  Timing around acquisitions of the index’s current constituents may be on the side of more changes. Just last week, Omnicom (OMC) and Interpublic (IPG) announced that the U.S. Federal Trade Commission has concluded its antitrust review of Omnicom’s proposed acquisition of Interpublic and reached agreement “on a mutually acceptable consent order”. The news represents a “notable step forward in the process of combining our companies”, said Philippe Krakowsky, CEO of Interpublic, while Omnicom CEO John Wren remarked “We continue to look forward to obtaining the remaining regulatory approvals and closing in the second half of this year, consistent with our expectations when we announced this transaction.”

PRICE ACTION: The selection and the snub have driven Datadog up about 12% in early Friday trading, while Robinhood is slumping 4%.