Every other structure in this course has been about collecting premium. A protective put pays it — you buy a put beneath shares you own, and it acts as insurance with a deductible.

It is worth understanding even if you never buy one, because it is the clearest illustration of what the premium you normally collect is actually being paid for.

Capped loss, uncapped gain

The payoff is the mirror of a covered call. A covered call caps your upside and leaves the downside open; a protective put caps the downside and leaves the upside open.

Below the strike the put gains dollar for dollar as the shares fall, so the two offset and your loss stops. Above it the put expires worthless and you keep every cent of the rally, less what the insurance cost.

Notice the first two rows are identical. Anywhere below $90 the loss is the same $1,320 — that flat floor is what you bought.

When it genuinely makes sense

A known event. Earnings, a court ruling, a regulatory decision. Buying protection for a specific window with a defined risk is a completely different proposition from buying it permanently.

A concentrated position you cannot sell. Restricted stock, a large low-basis holding where selling triggers a tax event. Here the put buys time.

Locking in a gain without realising it. A put below a large unrealised gain protects it while deferring the tax consequence.

In all three, the protection is bounded — a specific window or a specific problem. That is what makes the cost tolerable.

Financing it: the collar

The obvious response to a 13% annual cost is to make someone else pay for it. Sell a covered call above the market and use that premium to buy the put below it.

That structure is a collar, and it is what most people who want protection actually end up using — because it converts an expensive position into a roughly free one, at the cost of the upside.

What this teaches a premium seller

The most useful takeaway is not about buying puts at all.

Someone is paying that 13% a year, and when you sell a cash-secured put you are frequently on the other side of it. The persistent demand for downside protection is exactly why put skew exists and why the put side of a chain pays more than the call side at equal delta.

Premium selling is, structurally, the business of writing that insurance. This lesson is what the buyer sees — and understanding both sides is what makes the pricing make sense.

What can go wrong

Buying protection permanently. The cost exceeds most portfolios' returns.

Buying it after the fall. Implied volatility has already spiked, so the insurance is at its most expensive exactly when you want it.

Choosing a strike too far down. Cheap, and the deductible is so large the protection barely matters.

Forgetting it expires. Protection has a date; the position does not.