Polymarket Acquires Prediction Market API Startup Dome in Second Strategic Deal

Polymarket, the onchain prediction market platform valued at approximately $9 billion, has acquired Dome, a Y Combinator-backed startup that built a unified API for prediction markets. The transaction amount was not disclosed.

What Dome Does

Dome developed a unified application programming interface that connects developers to multiple prediction market platforms including Polymarket and Kalshi through a single integration point. Rather than requiring separate API integrations for each venue, Dome’s product normalises data feeds, provides real-time WebSocket streams, historical orderbook snapshots, and cross-platform market matching.

The startup was founded in 2025 by Kurush Dubash (CEO) and Kunal Roy (CTO), both former founding engineers at blockchain infrastructure firm Alchemy, where they spent over four years helping scale the company from 10 employees to 250 and a $10 billion valuation. During their time at Alchemy, both co-founders worked directly with Polymarket to build custom infrastructure that supported the platform’s scaling during the 2024 U.S. election cycle.

Funding History

• Y Combinator (Fall 2025 cohort): $500,000 standard deal, representing the company’s first disclosed funding.

• Seed Round: $4.7 million, as confirmed by co-founder Kunal Roy through public disclosures. The seed round was completed in late 2025.

PitchBook records Dome as a venture capital-backed company with total raised capital of $0.5 million and a last financing date of 14 November 2025, classified as a seed round. The total funding at $5.2 million the sum of the $500,000 YC investment and the $4.7 million seed round. The F6S platform separately lists Spot VC as a backer. At the time of acquisition, Dome had approximately three employees.

Polymarket’s Acquisition Strategy

This acquisition fits into a broader pattern of strategic growth through targeted acquisitions and partnerships. Key milestones in Polymarket‘s recent expansion include:

• July 2025: Polymarket acquired QCEX, a CFTC-licensed derivatives exchange and clearinghouse, for $112 million, paving the way for the platform’s re-entry into the U.S. market after a 2022 settlement with the CFTC that had resulted in a $1.4 million fine and the blocking of U.S. users.

• October 2025: Intercontinental Exchange (ICE), the parent company of the New York Stock Exchange, invested up to $2 billion in Polymarket at a pre-investment valuation of approximately $8 billion, bringing the post-money valuation to roughly $9 billion.

• Distribution partnerships: Polymarket has signed distribution agreements with Major League Soccer (MLS), the National Hockey League (NHL), and media platform Substack.

Polymarket’s total capital raised at approximately $2.26 billion, with a last financing classified as “Later Stage VC” dated 23 October 2025 and approximately 40 employees. By January 2026, secondary market valuations had reportedly pushed Polymarket’s implied valuation to $11.6 billion.

Investor Context

ICE, Polymarket’s most prominent backer, is a heavily regulated financial infrastructure company that owns the New York Stock Exchange. Its $2 billion investment in October 2025 included an agreement to become a global distributor of Polymarket’s to institutional investors, alongside a partnership on future tokenisation initiatives.

Earlier in 2025, Polymarket also received funding from 1789 Capital, a firm associated with Donald Trump Jr.. Prior venture capital backers have included Polychain Capital and Paradigm.

Market Context

The prediction market sector has experienced rapid expansion. Monthly volume grew from less than $100 million in early 2024 to more than $13 billion by the end of 2025, representing approximately 130-fold growth.

This wave of growth has also fueled adjacent infrastructure and tooling startups. For instance, Rhythmic Raises $4M to build analytics and execution tools for event-driven markets, highlighting investor appetite for platforms that improve liquidity, transparency, and developer access within the prediction ecosystem.

Industry projections from Citizens Financial Group estimate prediction market firm revenues could reach $10 billion by 2030, up from approximately $2 billion annually at present.

However, the sector faces challenges. Research from CertiK found that wash trading on Polymarket rose sharply in 2024. Sports markets now account for over 60% of Polymarket’s open interest, indicating concentration risk and heavy dependence on event-driven spikes. Regulatory clarity from U.S. authorities, particularly the DOJ and CFTC, remains a key variable for the sector’s long-term stability.​

What Comes Next

Polymarket has not disclosed an integration timeline for Dome’s technology. The company is reportedly exploring the possibility of raising additional capital at a valuation above its current $9 billion primary round. Whether the Dome acquisition can translate into measurable increases in trading volume, developer adoption, and platform stickiness particularly in non-sports categories remains to be determined.​