Prediction markets used to mean politics, sports, and crypto Up/Down contracts. In the last six weeks, Kalshi, Polymarket, and Limitless have each independently stood up real-money markets tied to individual stocks — not a stock-trading feature bolted onto a prediction-market platform, but event contracts settling on the same name-level tickers quant desks already track in equities.
This isn't a single-venue story. Each platform picked its own ticker list, and the overlap — and the gaps — are worth knowing before you build research or a backtest around any one of them.
What's actually confirmed, and from where
Convex Lake's own data-collection changelog is the clearest first-party record of this, since it tracks exactly when each venue's stock/index coverage went live and which tickers were included at that point:
- Kalshi — financial stock/index orderbook collectors added 2026-09-12: AAPL, AMZN, COIN, GOOGL, HOOD, META, MSFT, NFLX, NVDA, SPX, SPY, TSLA (12 tickers).
- Polymarket — financial stock/index orderbook collectors added the same day, 2026-09-12, with the identical 12-ticker list above.
- Limitless — financial stock/index orderbook collectors added 2026-10-07, with a different 12-ticker list: AAPL, AMZN, EQT, GOOGL, ITA, LMT, META, NVDA, OXY, SPCX, SPY, TSLA.
Line those two lists up and the overlap is AAPL, AMZN, GOOGL, META, NVDA, SPY — six names all three venues share. Kalshi and Polymarket additionally cover COIN, HOOD, MSFT, NFLX, SPX; Limitless instead covers EQT, ITA, LMT, OXY, SPCX (SpaceX-linked). That's a real, checkable difference in which stocks each platform treats as worth running markets on, not a rounding error.
Worth being precise about what this evidence does and doesn't establish. These ticker lists reflect what Convex Lake's own collectors capture, confirmed directly against its documentation — not an independently verified, complete snapshot of each venue's full live stock-market catalog at every moment. Each platform can add or drop tickers on its own timeline. Secondary sources confirm the broader pattern is real — Kalshi's data partnership with Barchart, real Polymarket markets on Apple's price thresholds and the "largest company by market cap" race between Nvidia, Apple, Alphabet, and Microsoft, and Limitless's own marketing describing stock and index coverage alongside crypto — but pinning down each venue's exact current full ticker list from outside sources alone wasn't reliable enough to assert here. Treat the three lists above as "confirmed covered as of the dates given," not "the complete current catalog."
Why this happened on three venues within four weeks of each other
None of these venues compete directly in the traditional sense — Kalshi is a CFTC-regulated exchange, Polymarket runs on Polygon with no US license, and Limitless matches orders on-chain on Base. But all three are chasing the same underlying demand: traders who want exposure to "will AAPL close above X" or "will NVDA stay the largest company by market cap" without opening a brokerage account or waiting for options expiry. That the exact same 12 stocks launched on Kalshi and Polymarket the same day suggests this is less about one platform copying another and more about a shared read on where attention — and volume — currently sits in equities.
Data quality pitfalls to watch for
Convex Lake's ticker list isn't necessarily each venue's full catalog. A venue can list a stock market without Convex Lake having a collector running against it yet, or vice versa drop a market Convex Lake's historical archive still has. Check the docs for current coverage before assuming a ticker is live.
"Finance" category labels don't always mean stocks. Polymarket's own "Finance" orderbook collectors (added 2026-10-07) cover HYPE, BNB, and DOGE — crypto tickers under a finance-labeled category, not equities. Don't conflate category labels across venues; verify what's actually underlying a given market before treating it as a stock contract.
Settlement mechanics differ by venue, same as every other market type. Kalshi settles against a regulated reference price under CFTC oversight; Polymarket and Limitless settle through their own oracle/resolution processes. A "stock market" on three different venues can still carry three different resolution-risk profiles — the venue doesn't change just because the underlying does.
Six-stock overlap, not twelve. If you're building a cross-venue comparison, only AAPL, AMZN, GOOGL, META, NVDA, and SPY currently have confirmed coverage on all three platforms per Convex Lake's own collectors. The other six tickers per venue are single-venue only.
Getting the data
Convex Lake collects orderbook data for all three venues' stock/index markets under the same schema it uses for crypto Up/Down and political markets — exchange=kalshi, exchange=polymarket, or exchange=limitless, with the relevant ticker. See the API docs for the current endpoint reference and ticker list, since both continue to expand.