Every symbol with at least 3 bars before 09:45 IST is measured against four thresholds. All four must pass for a stock to qualify.

In plain English: the stock is moving (gate 1), on real volume (gate 2), in one direction (gate 3), and the move is expanding, not stalling (gate 4).

Qualifying makes a stock a candidate. To become an actual trade, one of Engine 5's 12 pattern strategies has to fire on its 3-minute bars, and that signal has to pass the risk / portfolio / ML grader gates. If none of the 12 patterns matches during the session, the stock is watched but not traded.

The 12 patterns (in evaluation order):

1. VWAP Bounce — price touches VWAP from above/below with confirmation.
2. Opening Range Breakout — breaks the 09:15–09:30 range on volume.
3. Squeeze — Bollinger inside Keltner then expansion.
4. ABCD Pattern — measured-move continuation.
5. Bull Flag — pullback after impulsive up-leg, break of flag.
6. Bear Flag — mirror image, short side.
7. Momentum Reversal — exhaustion + turn against the day's trend.
8. Moving-Average Trend — EMA stack + pullback / continuation.
9. Support / Resistance — reaction at prior day's key levels.
10. Multi-Confluence Squeeze — squeeze + trend + volume in agreement (fallback).
11. Rally Short — fade parabolic up-moves.
12. Pivot Point — reaction at classical pivots.

Engine 5 blocks the "squeeze-pb" variant at every hour (the single filter that makes it Engine 5 vs Engine 25).