FactSet Integrates OptimX Bilateral Liquidity Into Portware EMS

OptimX Markets has partnered with FactSet to integrate its bilateral liquidity network directly into the Portware execution management system, giving institutional traders access to broker-driven liquidity without leaving their existing execution workflow, according to the partnership announcement. The integration supports both automated and manual trading workflows, with executions remaining fully attributed to the broker. OptimX executed its first live US equity trades in July 2025 and has since focused on expanding institutional reach through this partnership.

What Is Bilateral Liquidity?

Bilateral liquidity refers to controlled, permissioned trading relationships between buy-side firms and brokers, as opposed to exposing orders to broader venues such as exchanges or dark pools. This model is commonly used for large institutional trades where information leakage and market impact are key concerns.

By embedding OptimX into Portware, the partnership brings bilateral liquidity closer to the point where trading decisions are made. Traders can assess broker liquidity within the same system used for routing and execution strategy, reducing operational friction and eliminating the need to access separate platforms.

David Barnett, founder and chief executive of OptimX Markets, stated that embedding the network within Portware places it “directly into the execution layer, where trading decisions are made in real time.”

How the Integration Supports Broker Internalization

The integration is designed to keep broker attribution intact, allowing brokers to continue managing client relationships while accessing additional liquidity through OptimX. This is important for internalization, where brokers match client orders internally before routing to external markets.

Internalization can improve execution efficiency for brokers and clients when handled transparently, but it depends on strong workflow integration and clear controls. By operating inside Portware, the OptimX model allows buy-side firms to retain visibility over liquidity interaction while brokers retain control over how they engage with clients.

Robert Watts, director of strategy and product management at Portware, said the integration introduces “a differentiated source of bilateral liquidity directly into the EMS,” allowing traders to interact more deliberately with broker liquidity while maintaining transparency and control over execution.

Implications for Execution Technology

The partnership reflects a broader shift in institutional trading technology, where liquidity access is moving into core execution systems rather than remaining tied to standalone venues. For traders, this can reduce routing complexity and keep compliance controls within the existing workflow.

Liquidity providers connected to OptimX can now deliver high-touch and low-touch trading opportunities directly to buy-side desks using Portware. For institutional traders, embedding bilateral liquidity into execution systems provides more control over order exposure while helping brokers preserve direct client relationships and internalization economics.

The FactSet partnership gives OptimX access to buy-side desks already using Portware, reducing the need for new infrastructure. This collaboration follows earlier work by OptimX with PureStream Trading Technologies to improve liquidity discovery for block trading, pointing to growing demand for controlled execution channels as institutions seek alternatives to fragmented venues and traditional dark pools.

For FactSet, adding OptimX strengthens Portware’s role as a central access point for liquidity and execution tools. For OptimX, the deal provides distribution through an established institutional trading system rather than requiring traders to adopt a separate platform.