High, Mid and Low Frequency Shops
Trading firms are often sorted by how long their positions live — from microseconds at a high-frequency market maker to months at a long-only fund — and that holding period shapes almost everything else about how the firm is built.
Prerequisites: Systematic vs Discretionary Investing
Ask a recruiter "what does this firm trade" and you'll get an answer like equities or futures. Ask "how long does it hold a position" and you learn something more useful about what the job is actually like day to day, because holding period drives the technology stack, the skill set the firm hires for, and the pace of the work far more than the asset class does.
High-frequency (HFT) firms hold positions for fractions of a second to a few minutes. The edge is speed and market microstructure — being the first to react to an order-book change, capturing a fleeting mispricing between related instruments, or providing liquidity and earning the bid-ask spread thousands of times a day. The core skill set is low-latency systems programming, hardware-level networking and statistics on tick data; a strong HFT researcher may know less about macroeconomics than a hedge-fund analyst but knows exchange matching-engine behavior in exhaustive detail.
Mid-frequency firms hold positions from minutes to a few days. This is where most systematic equity and futures strategies live — statistical arbitrage, short-term momentum or reversal, and execution-aware trading that still cares about microstructure but doesn't need nanosecond speed. The skill set shifts toward statistics, feature engineering and backtesting discipline, since the strategy needs to be robust across many days of noisy data rather than exploiting one repeatable microsecond pattern.
Low-frequency firms hold positions from weeks to years — classic long-only asset management, most fundamental hedge funds, and systematic factor strategies like value or quality investing. Here the edge usually comes from a slower-moving insight — a mispriced fundamental, a persistent risk premium — and the job leans more on economic reasoning, valuation and portfolio construction than on split-second execution.
Why the boundary matters for a career
The three buckets barely overlap in what a "good candidate" looks like. A low-latency C++ engineer interviewing at an HFT firm and a fundamental analyst interviewing at a long-only fund are essentially different professions that both get called "trading." Moving from one bucket to another later in a career is possible but not trivial — the intuitions, tools and even the definition of "signal" differ enough that it's closer to a lateral move than a promotion.
Holding period — not asset class — is often the single biggest driver of what a trading job actually involves, because it determines whether the edge comes from speed, from statistics on short-term patterns, or from a slower fundamental or macro view.
When researching a firm, "how long do positions typically live" is a more informative interview question than "what do you trade" — it tells you what the day-to-day work and the required skill set will actually look like.
Related concepts
Practice in interviews
Further reading
- Narang, Inside the Black Box, ch. 2