US Equities

A market designed to help trades achieve best execution outcomes

Standard Workflow

A plug-and-play solution for broker algorithms, routers and DMA suites.

Limited Adverse Selection

Time randomized periodic auctions reduce gamability and help to align like-minded traders on short time horizons.

Optimize for Execution Quality

OneChronos matches orders independent of when they arrive in the order book. It operates a “Smart Market” which leverages optimization techniques to find matching solutions that solve for outcome traders care about.

Information Leakage Protection on a Pre and Post Trade Basis

No data feeds or pre-trade transparency facilitate a truly dark trading experience. Multi-lateral prints are aggregated when disseminated to the market helping to mitigate information leakage even after trades hit the tape.

Industry Recognition

Innovation in a competitive and efficient marketplace

OneChronos operates a dark U.S. equities ATS that facilitates trading by hosting auctions on average 10-20 times per second throughout the trading day. Within each auction, instead of using price/time priority OneChronos matches inbound orders in a manner that maximizes the notional price improvement achievable across participants creating a new regime of competition that leads to unique liquidity opportunities and high quality performance.

The platform's seamless integration with existing market structure has driven rapid adoption, enabling firms to easily access enhanced execution capabilities through their current workflows. In addition to growth of adoption, our model has received accolades from our customers and industry participants:

  • 2025 TabbFORUM NOVA Award for Top Innovators Across Financial Markets
  • 2024 Award of Crossing Network of the Year from The Trade
  • 2024 Award for Innovation in Trading and Finance from the Security Traders Association of New York

Products

Nexus

Nexus is our custom counterparty offering (sometimes known in the market as "private rooms"), accessed through your routing broker. It addresses growing user demand for bilateral liquidity, one-to-many trading, and outsourced matching engine technology. Our approach is lightweight and flexible, with numerous customizable configurations leveraging our best-in-class matching algorithm. Nexus executions have real-time transparency to participants, and its design is thoroughly described in our Form ATS-N.

Conditionals

Conditional orders have helped traders source block liquidity and reduce the opportunity cost often associated with fragmentation. We've delivered a product that works well for these use cases while creating additional optionality and unique liquidity on the OneChronos platform.

Pairs

Expressive Bidding (EB) is one of the defining features of a Smart Market, providing the ability to express highly customizable execution preferences over one or more securities. Pairs EB, our first live EB product, provides a very intuitive use case for trading two assets atomically and is designed to complement broker pairs algorithms. Pairs EB eliminates the legging risk associated with trading merger arb deals, dual-class shares, beta / delta hedging, and relative value trading, marking the beginning of our multi-symbol journey.

FAQ

Frequently Asked Questions

If you can't find what you're looking for, email our support team and if you're lucky someone will get back to you.

Auction Mechanics, Match Procedure & Order Types

    How are OneChronos periodic auctions initiated? And at what frequency?

    How are orders matched on OneChronos ATS? What is the “match priority” model?

    What order types are available at OneChronos?

Trading at OneChronos

    Can orders persist for multiple OneChronos auctions? For example, those not matched or not fully executed in a OneChronos auction.

    What types of participants are anticipated to use OneChronos?

    How does the ATS determine which orders are eligible in an auction? What happens to orders received after the auction cutoff?

Trade Reporting, Visibility & Transparency

    Where does OneChronos ATS print its trades?

    What data is disseminated through public trading reporting?

    Where can I view Form ATS-N for OneChronos ATS?

Data Center, Market Data & Routing

    Where is the OneChronos matching engine located?

    Does OneChronos ATS route any orders externally? For example, those not matched in a OneChronos auction.

    How is NBBO calculated?

Connectivity

    How can OneChronos be accessed?

    Are there any special requirements for order submission via FIX?

    What are the hours of operation for OneChronos ATS?

Expressive Bidding

    What is Expressive Bidding? How should I consider if Expressive Bidding is relevant for how I trade?

    Is Expressive Bidding required to trade at OneChronos?

    Can / Does my broker use Expressive Bidding to complement its trading algorithm or smart routing strategies?