# Prediction Market Arbitrage: Three Live Opportunities on July 13, 2026 (July 13, 2026)
_Our cross-venue engine has surfaced three live prediction market arbitrage opportunities as of July 13, 2026, allowing users to lock in guaranteed profits._
**Published:** 2026-07-13
**Source:** https://www.startuphub.ai/ai-news/prediction-markets/2026/prediction-market-arbitrage-three-live-opportunities-on-july-13-2026-july-13-2026
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StartupHub.ai's proprietary cross-venue engine has identified multiple prediction market arbitrage opportunities today, July 13, 2026. These opportunities arise when the same real-world event is priced differently across various platforms such as Polymarket, Kalshi/Robinhood, and PredictIt, creating a scenario where buying 'YES' on one venue and 'NO' on another costs less than $1 combined.

An arbitrage lock means you can simultaneously bet on both outcomes of an event for a total cost under $1, guaranteeing a profit regardless of the event's resolution. While our engine continuously monitors for these spreads, they can close rapidly due to market movements. It is also important to consider potential fees, KYC requirements, and withdrawal limits that may impact net returns.

Arbitrage ROI by event. Who will win the 2028 US pr...: ROI % 4. 2028 Democratic presidentia...: ROI % 3.57. 2028 Democratic presidentia...: ROI % 3.15. Cross-venue spreads on July 13, 2026. Source: StartupHub.ai arbitrage engine.

**Live arbitrage right now** These update automatically. Tap a leg to open the venue. Not financial advice.

- **Who will win the 2028 US presidential election?, Gavin Newsom**. Arbitrage: 4.0% ROI, locks 4c per $1. Buy YES on [Polymarket](https://polymarket.com/event/will-gavin-newsom-win-the-2028-us-presidential-election) at 12c, buy NO on [PredictIt](https://www.predictit.org/markets/detail/8171/Who-will-win-the-2028-US-presidential-election) at 84c.
- **2028 Democratic presidential nominee Will Rahm Emanuel be the Democratic Presidential nominee in 2028?**. Arbitrage: 3.6% ROI, locks 3c per $1. Buy YES on [Polymarket](https://polymarket.com/event/will-rahm-emanuel-win-the-2028-democratic-presidential-nomination-299) at 2c, buy NO on [Kalshi / Robinhood](https://kalshi.com/markets/kxpresnomd) at 95c.
- **2028 Democratic presidential nominee Will Mark Kelly be the Democratic Presidential nominee in 2028?**. Arbitrage: 3.1% ROI, locks 3c per $1. Buy YES on [Polymarket](https://polymarket.com/event/will-mark-kelly-win-the-2028-democratic-presidential-nomination-479) at 1c, buy NO on [PredictIt](https://www.predictit.org/markets/detail/8153/Who-will-win-the-2028-Democratic-presidential-nomination) at 96c.

[See the full live arbitrage board](https://www.startuphub.ai/arbitrage) or poll the free [JSON API](https://www.startuphub.ai/api/v1/arbitrage).

## Track these live, or poll the free API

The board above refreshes on its own, so this page stays current long after today. The full cross-venue feed lives on the [arbitrage board](https://www.startuphub.ai/arbitrage), and every match is also a free JSON API and an MCP tool, so a trading agent can poll live Polymarket, Kalshi and PredictIt arbitrage opportunities and act on them.

```
curl https://www.startuphub.ai/api/v1/arbitrage?arbs_only=1
```

[Read the arbitrage API reference](https://www.startuphub.ai/api-docs/reference/arbitrage) or open the [live JSON endpoint](https://www.startuphub.ai/api/v1/arbitrage).

*Informational feed, not financial advice. Live arbitrages are often fleeting, and fees, gas, KYC and withdrawal limits eat into the spread. Verify each market’s resolution rules and costs before trading.*
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Original analysis from [startuphub.ai](https://www.startuphub.ai), the #1 AI startup directory.