📊 Kalshi and Polymarket no longer #1?

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Here’s what we got for you today:

Just when everyone thought no one could dethrone Kalshi and Polymarket in the prediction market race, a new competitor has emerged.

It’s name? Opinion. Launched exclusively on BNB Chain in October this year, the decentralized prediction market has quickly reached $1.43B in weekly notional volume, beating out Polymarket ($1.19B) and Kalshi ($1.34B) this past week.

Opinion’s roots stem from YZi Labs (formerly Binance Labs) which awarded them $5M in seed funding. Some view Opinion as a Polymarket copycat, built with almost identical functionality on the blockchain.

While Opinion may have topped weekly volume charts, some argue that open interest is a better indicator of prediction market performance.

Here’s a simple example to explain the difference:

When looking at the open interest numbers on Dec 24 among the three platforms, we notice a different story:

Zoom out: Opinion’s volume surge is impressive, but Kalshi and Polymarket still hold 5x more capital in committed bets. Only time will tell if Opinion can maintain this momentum, but for now it seems like Kalshi and Polymarket are still in the lead.

Side note: For developers wanting to build on the new exchange, Opinion has opened a builder program with over $1M in grants available.

Earlier this week, Rainbow announced their partnership with Polymarket, allowing IOS users to trade on their favorite events in sports, politics, crypto, culture, & more, all natively in their wallets. Today, that privilege was also extended to Android users (yes, they should be able to trade too).

Rainbow isn’t the only wallet allowing its users to predict the future. Today, Solflare announced that they are the newest member in the prediction markets arena, partnering with Polymarket rival Kalshi to allow users to trade natively without fees.

Why should we care? Both are strong signals that indicate prediction markets are moving away from standalone apps to wallet-native experiences. No new onboarding, no need for separate accounts.

No surprise that Polymarket, with its strong crypto-native reputation, partnered with Rainbow to bring mobile trading to a much broader audience. Kalshi’s partnership with Solflare should similarly drive more participation and liquidity across DeFi markets.

More broadly, these partnerships signal something bigger. Prediction markets are no longer niche. They’re becoming part of the mainstream trading experience, with more users, deeper liquidity, and more active markets. We absolutely LOVE to see it. 📈

Over the last couple days, three Polymarket accounts pumped the price of the “Will Trump meet with Zelenskyy by Dec 31” market from near 0% all the way to 90%. The catch? No news related to a meeting had been released.

Each account was created only 24 hours before trading, funded with nearly identical amounts (5k, 5k, 4.9k USDC), and placed only on this single market.

After these bets were placed, news broke that Trump is scheduled to meet with Zelenskyy this Sunday. While there's no hard proof of insider trading, these accusations have become increasingly common on prediction markets as prices often surge right before news breaks.

The accounts in question:

A problem to be solved: insiders are a real threat to prediction market fairness. Although they help push markets toward true odds, it comes at the expense of regular traders who don't have access to the same info.