The question every small-cap trader asks

"How do I find the runners before they run?" It's the first question and often the wrong one. The honest answer is: you don't find the runner. You find a pool of 10–30 candidates every morning, and you wait for the tape to confirm which ones have genuine follow-through. Most mornings, 2–3 of them actually run. The rest fade.

This guide walks through the five pre-market signals BullAlert's scanner weights most heavily — the signals that separate tomorrow's gappers from the noise. Nothing here is financial advice. Always do your own DD before making any investment decision.

Signal 1: Relative volume on the gap

A stock up 40% pre-market on 50k shares is a nothing-burger. The same move on 5 million shares is a story. Volume is the first filter because it's the only pre-market signal that's actually hard to fake.

The metric: pre-market RVOL computed against a pre-market-specific baseline (not the full day). BullAlert uses ~10% of average daily volume as the "expected" pre-market number. A stock at 5× pre-market RVOL has already traded 5 times its usual pre-market volume — that means real participation, not a lone order.

Read our deep dive on RVOL for why the naive formula (today / avg) is wrong and how to compute it properly.

Signal 2: Gap-and-hold structure

Not all gaps are created equal. Watch the first 30 minutes after the gap:

Gap and go: Gap up, hold the gap high, push higher on rising volume. Strongest setup.
Gap and fill: Gap up, immediately fade back through the opening price. Weak. Skip.
Gap and chop: Gap up, then trade in a tight range for an hour. Undecided. Wait for the break.

A stock that gaps 30% and then makes a higher high in the next 30 minutes is showing follow- through. A stock that gaps 30% and immediately red-prints is showing distribution. The tape tells you which — read it, don't guess. For the full breakdown, see Gap-and-Go: Anatomy of a Pre-Market Gapper.

Signal 3: Float and share structure

Small float = less supply = faster moves. BullAlert's scanner pays special attention to floats under 20 million shares, with the sweet spot around 2–10 million. A 5M-float stock can move 50% on a few hundred thousand shares of buying — because there simply isn't that much available to sell.

Beware the inverse: very low floats (under 1M shares) are too thin to trade safely. Your order becomes the order flow. We filter those out.

We never display raw float numbers to users — small-cap float data is easily manipulated and often out of date. Instead, float is bucketed (NANO / MICRO / SMALL / MEDIUM / LARGE) and used as one input to the scoring engine.

Signal 4: Pre-market high respected

Here's a simple rule that eliminates 80% of bad pre-market setups: watch whether the stock respects its pre-market high.

If the pre-market high held for the last 90 minutes and price is consolidating just below it on rising volume, the stock is coiling for a breakout. That's strong.

If price punched through the pre-market high once, fell back, and is now meandering — the best move already happened pre-market. That's a late catch waiting to happen. Skip.

Signal 5: Sector or theme context

The fifth signal is the softest but often the most predictive: is there a thematic reason for institutional money to be interested? FDA calendar day. Earnings week for a sector. Geopolitical catalyst (defense, oil, uranium). Social-media squeeze chatter.

A single small cap moving in isolation is usually retail excitement. A small cap moving in sympathy with 5 other names in the same sector is institutional rotation. The second kind tends to have real follow-through. The first kind tends to fade.

BullAlert's scanner weights community spread (how many independent social sources are talking about a ticker) as a proxy for this signal. It's imperfect — social chatter can be manufactured — but combined with RVOL and structure, it helps separate the sympathy plays from the one-offs.

Putting the signals together

Each signal on its own is noise. Together they stack:

High pre-market RVOL (5×+) → something real is happening
Gap-and-hold structure → follow-through is confirmed, not just a spike
Small float (2–10M) → supply constraint amplifies the move
Pre-market high respected → buyers are still in control
Sector or theme context → institutional rotation, not retail noise

A stock checking 4 or 5 of these is in the BullAlert scanner's premium tier. A stock checking 2 or fewer is filtered out. That's the difference between a watchlist of 10 actionable candidates and a watchlist of 100 "interesting" names.

What the scanner actually does with this

BullAlert runs these filters every 5 minutes during extended hours. When a stock passes the premium gate, it fires a real-time alert tagged by session, score, and pattern. Paid users see it live; the public alert history shows what we caught on any given day.

From there, Edgar — our paper-trading bot — acts on the alerts with simulated capital and logs the entries and exits in a diary. That's how you study whether a particular signal combo actually produced follow-through on that day's tape. No guessing, no cherry-picking — the trades are timestamped and public.

How to Find Stocks Before They Run — 5 Pre-Market Signals