TOTAL VOLUME:
$134.1b
24H VOL:
$141,541,542
24H TRANSACTIONS:
2,388,728,490
OPEN INTEREST:
$1,440,096,988
406,065
Markets across
30,522
events
MATCHED EVENTS:
2,692
PLATFORM COVERAGE:
5
Polymarket:
39%
VS.
Kalshi:
61%
Closed: Jul 1, 10:00 AM EST
Kalshi
This market tracks whether specific publicly-traded companies will join the S&P 500 index during the April–June 2026 period. On Kalshi, Alnylam Pharmaceuticals has a 21.0% probability of addition, while Reddit carries a 14.0% probability. The market resolves based on official S&P Dow Jones Indices announcements of index inclusions during Q2 2026, with final resolution by July 1, 2026. Watch for S&P index reconstitution announcements throughout April, May, and June 2026, as these typically occur on specific trading days following market close.
A company's addition to the S&P 500 resolves to Yes if either the index administrator officially announces the membership change or the change takes effect during April 1 through June 30, 2026, whichever occurs first. The effective date need not fall within the specified period; only the announcement or implementation must occur during this timeframe. Temporary suspensions do not constitute removal unless explicitly designated as permanent by the index administrator. If an announced addition is subsequently reversed due to error within the time period, the Exchange will determine resolution at its discretion. For companies undergoing mergers, acquisitions, or restructuring, removal from the index due to such corporate actions constitutes removal for purposes of this market. If a spin-off or successor entity is immediately added in place of the original company, the original company is still considered removed. Regular scheduled rebalancing events count as additions or removals if the company's membership status changes during such rebalancing.
Prediction market odds on Kalshi reflect real-money trader conviction and differ from traditional analyst forecasts, which rely on historical S&P Dow Jones Indices selection patterns and qualitative assessments. Markets price in live information about company fundamentals, market cap thresholds, and liquidity requirements more dynamically than static analyst reports. While analysts may emphasize regulatory or accounting factors, prediction markets aggregate distributed knowledge from active traders who face direct financial consequences for accuracy, often producing complementary but distinct probability estimates for Q2 2026 additions.
The market resolves on Jul 1, 2026, after the S&P 500 index composition window for Q2 2026 closes. Outcome determination depends on official announcements from S&P Dow Jones Indices regarding which companies are added to the index during that quarter. Each contract outcome is binary: either a specific company is confirmed as added to the S&P 500 in Q2 2026, or it is not. Resolution follows the index operator's public statements and filings.
Key catalysts include quarterly earnings reports that affect market capitalization and trading volume eligibility, analyst rating changes, and corporate governance announcements. Regulatory filings, debt issuances, or strategic partnerships can shift S&P Dow Jones Indices selection criteria assessments. Broader market volatility and sector rotation also influence candidate valuations. Media coverage of index inclusion speculation, management commentary on public market readiness, and changes to competitor eligibility all drive trader sentiment and contract prices through Q2 2026.