ZEBRA (Zero Extrinsic Back Ratio)
A ratio of two purchased ITM calls against one sold ATM call, calibrated so that net extrinsic value is zero: it replicates 100 shares without paying time decay.
Profit / Loss Diagram
Bullish ZEBRA at expiration
What is this strategy?
ZEBRA stands for Zero Extrinsic Back Ratio, and the name describes exactly what it does. In its bullish version you buy two in-the-money calls with a delta of roughly 0.70 and sell one at-the-money call. The sum of the deltas — 0.70 + 0.70 − 0.50 — comes to about 0.90, and with fine strike adjustment it can be taken to 1.00: the structure behaves like 100 shares of the underlying. The key is the premium calibration: the extrinsic value of the two purchased calls is offset by that of the sold call, leaving net extrinsic value close to zero.
The consequence of that design is what makes the structure interesting: paying no net extrinsic value, the position <em>suffers no time decay</em> and is practically insensitive to changes in implied volatility. It therefore eliminates the two engines that cause traders who get the direction right to lose money on timing or on buying with inflated volatility. What remains is pure directional exposure, with the added benefit that loss is capped at the debit paid — unlike a stock position.
Against buying 100 shares, ZEBRA requires less capital and caps the loss; against buying a simple call, it eliminates theta and vega in exchange for a larger debit. Its limitations are specific: it needs a liquid option chain with enough strikes to calibrate properly, it involves three legs with their commissions and spreads, and it collects no dividends. A bearish version also exists, with two purchased in-the-money puts and one sold at-the-money put.
Construction
| Action | Instrument | Strike | Expiration | Example |
|---|---|---|---|---|
| BUY | 2 Calls (ITM) | Delta ≈ 0.70 | 45-90 DTE | +2 XYZ 90 Call |
| SELL | 1 Call (ATM) | Delta ≈ 0.50 | Same expiry | -1 XYZ 100 Call |
Example
Scenario: XYZ at $100, a bullish thesis over two months. You want exposure equivalent to 100 shares without paying decay or depending on implied volatility.
- Calls Purchased (ITM) +2 XYZ 90 Call @ $12.40 each
- Call Sold (ATM) -1 XYZ 100 Call @ $4.80
- Net Debit $2,000 (24.80 − 4.80 × 100)
- Net Delta ≈ 0.90 — it behaves like 90 shares
- Net Extrinsic ≈ $0 — there is no decay to pay
- Maximum Loss $2,000 (the net debit)
- Maximum Gain Unlimited, with a slope equivalent to 90-100 shares
- Versus shares $2,000 against $10,000 for 100 shares
- Scenario: XYZ at $110 Gain of around $900-1,000, similar to owning the shares
- Scenario: XYZ at $85 Loss capped at $2,000, against $1,500 and no floor with shares
The Greeks
Two 0.70-delta calls minus one 0.50-delta call gives a net close to 0.90. Adjusting the strikes it can be fine-tuned to 1.00, at which point the structure replicates a 100-share position exactly.
The extrinsic value of the two purchased calls is offset by that of the sold call, leaving net decay of practically zero. It is the feature that gives the structure its name and its main advantage over buying a call.
With no net extrinsic value, a change in implied volatility barely affects the position. You can get the direction right without an IV collapse ruining the trade.
The two purchased calls contribute more gamma than the sold one, so delta improves as price rises. The convexity is modest but favourable.
Position Management
- 01 Treat It Like a Stock Position With no theta and no vega, management simplifies: the only relevant variable is price. Apply the same profit-taking and invalidation levels you would use on the stock position it replaces.
- 02 Watch the Expiration Unlike shares, the structure expires. With 21-30 days left, the extrinsic balance deteriorates and the short leg’s gamma starts to weigh. Roll to a later expiration if the thesis is still valid.
- 03 Recalibrate on a Large Move A big move changes the deltas and the structure stops replicating 100 shares. If net delta drifts far from target, closing and reopening with updated strikes restores the profile.
- 04 Mind Assignment on the Short Leg The sold call is at-the-money and can be assigned, especially before a dividend. If that happens you are short 100 shares covered by your two long calls: check the dividend calendar before opening.
- 05 Close All Three Legs at Once Unwinding the structure piecemeal leaves unbalanced positions with a different risk profile than intended. Use a combination order to close everything simultaneously.