Sizing a short: the stop is above the entry, and the losing side is the growing side
Everything about risk is mirrored and one thing is not: a short that moves against you gets bigger. Sizing starts from the hard stop and stays smaller than the long side's numbers.
Key takeaway
- The stop sits above the entry and the shipped rule caps the loss at 10% — size is the risk budget divided by that distance
- A short is a borrowed position: it requires margin, accrues borrow fees, owes any dividends, and can be recalled
- The asymmetry compounds against you — a rising price grows the position as it grows the loss — so shorts run smaller than the equivalent long
The stop is above the entry, and it is the size calculation
A short position profits as price falls and loses as price rises, so every risk number flips sides: the stop goes above the entry, and 'how far to my stop' is measured upward. The shipped rule is a hard stop 10% above the entry price. Size follows from one division — the account fraction you will lose if the stop is hit, divided by that 10%.
Notice what the 10% stop is not: it is not the cover rule. The falling 30-week average may sit 20% or more above a breakdown entry, and using the reclaim as the only exit would mean accepting that entire distance as risk — on an instrument where the loss does not stop there. The hard stop caps the failure case; the reclaim rule ends the position that worked and then stopped working. They are different exits at different distances, exactly as the long system's initial stop and stage exit are.
On a long, the worst case is bounded by zero. On a short there is no zero above you. The hard stop is not a preference or a tuning choice — it is the boundary that makes the position finite, and the one rule in this system that must never be waived.
A short is a borrowed position, and the borrow has terms
To sell a stock you do not own, your broker borrows the shares from another account, sells them, and holds the proceeds against your obligation to return the shares later. That plumbing has costs and conditions that a long position never meets, and each one belongs in the plan rather than in the surprise column.
| Mechanic | What it is | What it means for you |
|---|---|---|
| Margin account | Shorting is only possible on margin, with a maintenance requirement | A rising price can force deposits — or forced covering — before your stop is reached |
| Borrow fee | An annualised rate paid while the borrow is open | Cheap on liquid large caps, punitive on crowded shorts; it is a running cost against a capped maximum gain |
| Dividends | Any dividend paid while short is owed by you to the lender | A dividend date inside your holding window is a known, scheduled cost — check before entry |
| Recall | The lender can demand the shares back at any time | You can be forced to cover at the worst moment, through no signal of your own |
None of these mechanics appears on the chart, and every one of them can end the trade. This is the concrete sense in which a short is not a mirrored long: the long side's worst operational surprise is a fill slightly past the stop, while the short side's is being removed from a working position by someone else's phone call.
The losing side is the growing side — so shorts run smaller
Hold the mechanics in one picture. A long that falls 30% is now a smaller position; left alone, it shrinks toward irrelevance. A short that rises 30% against you is now a bigger position — the exposure grew exactly as the loss did, and the margin requirement grew with it. The long side's losers deflate themselves; the short side's losers inflate themselves.
- Size below the long system's numbers. If your long positions risk one percent, the equivalent short deserves less — the tail beyond the stop is fatter, and gaps through a stop on a short have no ceiling.
- Cap gross short exposure across the book. Simultaneous Stage 4 signals cluster in bear phases, and a book of shorts into one squeeze-day rally is a single correlated loss wearing several tickers.
- Never add to a losing short. Averaging into a rising short grows the fastest-growing thing you own. The only additions this method contemplates are to positions already working, on fresh breakdowns.
The capped upside completes the arithmetic. A short's maximum gain is 100% — the fall to zero — while its loss is unbounded; the long side enjoys the reverse. A system with this payoff shape survives on modest size and ruthless stops or it does not survive, and that is a statement about arithmetic, not temperament.
Common questions
- Could I use put options instead of shorting the stock?
- Puts bound the loss at the premium, which removes the unbounded tail — and replaces it with different problems: the premium decays daily, the position expires, and a decline that arrives two months late pays nothing. It is a legitimate expression of a Stage 4 view, but it is a different system with a clock in it, not this system with the risk removed.
- Why a percentage stop here when other systems in the library use ATR?
- The shipped rule is a flat 10% above entry — simple, unambiguous, and calibrated to the swing size of liquid large caps. A volatility-denominated stop would adapt better across quiet and wild names; it would also add a parameter to the one rule that must never be reasoned with mid-trade. For the instrument list this system targets, the flat cap does the essential job: it makes the loss finite.
- What does 'while positioned' mean for time commitment?
- Twenty minutes a day when a short is open — checking price against both exits, the margin position, and the borrow status. Flat, the system needs only a periodic scan for new Stage 4 candidates. The asymmetric attention is itself a design fact: a long stage position tolerates a week of neglect, and a short does not.
The ideas behind it
This system assumes you already know these. Each one is explained from scratch in Investing 101.
These are documented methods described for study. Nothing here is investment advice, a recommendation, or a claim about future returns — every system on this page has losing periods, and the pages say where.
Reading about a system is not having one.
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