The LSE Directory / Trading software
Portfolio123 is a web-based quantitative research and portfolio-management platform for building, backtesting, and running rules-based (systematic) equity and ETF strategies. Users define a multifactor Ranking System from fundamental and technical data, screen and backtest it against decades of point-in-time history, then optionally push signals into a live simulated or brokerage-linked portfolio. The whole workflow runs in the browser; no local software installation or programming is required to use the core Research and Screener tools. The platform's central differentiator is data discipline: fundamentals, analyst estimates, corporate actions, and index or sector classifications are stored point-in-time, so a backtest sees only the information that would have been available on each historical date, addressing the survivorship and look-ahead bias that affects simpler screener tools. Coverage runs to roughly 15,000 current US, Canadian and European stocks, plus thousands of delisted names for historical testing, drawn primarily from FactSet, with S&P Global Compustat and CapitalIQ datasets available under separate license. Beyond the no-code interface, Portfolio123 offers a DataMiner/API tier for programmatic access to the same point-in-time factors and simulation engine, a machine-learning ranking add-on called AI Factor, and order-routing links to brokers including Interactive Brokers and Tradier, so a validated strategy can be automated rather than only studied. This positions it between free stock screeners and the in-house quant infrastructure of larger asset managers, serving individual systematic investors, registered investment advisors, and quant researchers who want the workflow without building it from code. The company was founded in 2004 by Marco Salerno, who had worked in the hedge fund industry, including at Citadel, before building the automated strategy tools that became Portfolio123; he remains the company's CEO. Portfolio123 is privately held and based in Chicago, Illinois. A separate SEC-registered affiliate, Portfolio123 Securities LLC (trading as Portfolio123 Advisor, CRD number 283900, a Delaware corporation formed in 2016), offers discretionary and nondiscretionary portfolio management and trading-signal subscription services; its controlling interest is held by Salerno through Prism Research, Inc. The company states its tools have been used in MBA coursework at institutions including Stanford's Graduate School of Business, and that its user base has included asset managers such as National Bank and Morgan Stanley alongside individual subscribers. As of mid-2026 the company keeps a low-friction entry point for individual users, a 30-day free trial requiring no credit card and retail research plans starting near $25 a month, alongside custom-quoted API and professional access for asset managers and research providers. That split between self-serve retail pricing and bespoke institutional terms has remained a core part of its go-to-market since the platform's early years as a do-it-yourself quant research community.
