Consolidation Pressure in Prediction Markets
Dome
As prediction markets get bigger, control over the best liquidity and the cleanest official data starts to matter more than simple aggregation. Today a startup can win by stitching together feeds from Polymarket, Kalshi, and newer venues, but the strongest platforms are already turning volume into leverage by becoming the place partners route orders, embed odds, and license official market data. That makes small API vendors easier to squeeze, acquire, or route around.
-
The product gap Dome fills is real because the market is still fragmented at the technical level. Polymarket is on-chain and easier to read directly from blockchain data, while Kalshi runs a closed, regulated stack, so builders need normalization before they can compare prices, history, and order books in one schema.
-
But concentration is rising at the liquidity layer. Internal research shows Kalshi did about $17B of 2025 volume and Polymarket about $22B, while broader market activity has stayed elevated after the 2024 election and shifted heavily into sports. When most trading sits on two venues, those venues gain more power to pick preferred distributors.
-
The next step is vertical integration. Kalshi and Polymarket already offer their own APIs, and the category is moving toward direct distribution through brokers, media, sportsbooks, and leagues. Once a platform can provide official prices, order routing, and branded embeds itself, third party data resellers look less like core infrastructure and more like optional middleware.
The likely end state looks like equities and sports data combined, a few dominant venues, a long tail of niche markets, and a thinner middle layer of independents. The winners in data will either own exclusive access to important order flow, or become the default integration layer before the big venues fully lock up partnerships and distribution.