Put option

Last updated

In finance, a put or put option is a derivative instrument in financial markets that gives the holder (i.e. the purchaser of the put option) the right to sell an asset (the underlying), at a specified price (the strike), by (or on) a specified date (the expiry or maturity) to the writer (i.e. seller) of the put. The purchase of a put option is interpreted as a negative sentiment about the future value of the underlying stock. [1] The term "put" comes from the fact that the owner has the right to "put up for sale" the stock or index.

Contents

Puts may also be combined with other derivatives as part of more complex investment strategies, and in particular, may be useful for hedging. Holding a European put option is equivalent to holding the corresponding call option and selling an appropriate forward contract. This equivalence is called "put-call parity".

Put options are most commonly used in the stock market to protect against a fall in the price of a stock below a specified price. If the price of the stock declines below the strike price, the holder of the put has the right, but not the obligation, to sell the asset at the strike price, while the seller of the put has the obligation to purchase the asset at the strike price if the owner uses the right to do so (the holder is said to exercise the option). In this way the buyer of the put will receive at least the strike price specified, even if the asset is currently worthless.

If the strike is K, and at time t the value of the underlying is S(t), then in an American option the buyer can exercise the put for a payout of K−S(t) any time until the option's maturity date T. The put yields a positive return only if the underlying price falls below the strike when the option is exercised. A European option can only be exercised at time T rather than at any time until T, and a Bermudan option can be exercised only on specific dates listed in the terms of the contract. If the option is not exercised by maturity, it expires worthless. (The buyer will not usually exercise the option at an allowable date if the price of the underlying is greater than K.)

The most obvious use of a put option is as a type of insurance. In the protective put strategy, the investor buys enough puts to cover their holdings of the underlying so that if the price of the underlying falls sharply, they can still sell it at the strike price. Another use is for speculation: an investor can take a short position in the underlying stock without trading in it directly.

Instrument models

The terms for exercising the option's right to sell it differ depending on option style. A European put option allows the holder to exercise the put option for a short period of time right before expiration, while an American put option allows exercise at any time before expiration.

The most widely traded put options are on stocks/equities, but they are traded on many other instruments such as interest rates (see interest rate floor) or commodities.

The put buyer either believes that the underlying asset's price will fall by the exercise date or hopes to protect a long position in it. The advantage of buying a put over short selling the asset is that the option owner's risk of loss is limited to the premium paid for it, whereas the asset short seller's risk of loss is unlimited (its price can rise greatly, in fact, in theory it can rise infinitely, and such a rise is the short seller's loss). The put buyer's prospect (risk) of gain is limited to the option's strike price less the underlying's spot price and the premium/fee paid for it.

The put 'writer' believes that the underlying security's price will rise, not fall. The writer sells the put to collect the premium. The put writer's total potential loss is limited to the put's strike price less the spot and premium already received. Puts can be used also to limit the writer's portfolio risk and may be part of an options spread.

The put buyer/owner is short on the underlying asset of the put, but long on the put option itself. That is, the buyer wants the value of the put option to increase by a decline in the price of the underlying asset below the strike price. The writer (seller) of a put is long on the underlying asset and short on the put option itself. That is, the seller wants the option to become worthless by an increase in the price of the underlying asset above the strike price. Generally, a put option that is purchased is referred to as a long put and a put option that is sold is referred to as a short put.

A naked put, also called an uncovered put, is a put option whose writer (the seller) does not have a position in the underlying stock or other instrument. This strategy is best used by investors who want to accumulate a position in the underlying stock, but only if the price is low enough. If the buyer fails to exercise the options, then the writer keeps the option premium. If the underlying stock's market price is below the option's strike price when expiration arrives, the option owner (buyer) can exercise the put option, forcing the writer to buy the underlying stock at the strike price. That allows the exerciser (buyer) to profit from the difference between the stock's market price and the option's strike price. But if the stock's market price is above the option's strike price at the end of expiration day, the option expires worthless, and the owner's loss is limited to the premium (fee) paid for it (the writer's profit).

The seller's potential loss on a naked put can be substantial. If the stock falls all the way to zero (bankruptcy), his loss is equal to the strike price (at which he must buy the stock to cover the option) minus the premium received. The potential upside is the premium received when selling the option: if the stock price is above the strike price at expiration, the option seller keeps the premium, and the option expires worthless. During the option's lifetime, if the stock moves lower, the option's premium may increase (depending on how far the stock falls and how much time passes). If it does, it becomes more costly to close the position (repurchase the put, sold earlier), resulting in a loss. If the stock price completely collapses before the put position is closed, the put writer potentially can face catastrophic loss. In order to protect the put buyer from default, the put writer is required to post margin. The put buyer does not need to post margin because the buyer would not exercise the option if it had a negative payoff.

Example of a put option on a stock

Payoff from buying a put. Long put option.svg
Payoff from buying a put.
Payoff from writing a put. Short put option.svg
Payoff from writing a put.

Buying a put

A buyer thinks the price of a stock will decrease. They pay a premium that they will never get back, unless it is sold before it expires. The buyer has the right to sell the stock at the strike price.

Writing a put

The writer receives a premium from the buyer. If the buyer exercises their option, the writer will buy the stock at the strike price. If the buyer does not exercise their option, the writer's profit is the premium.

Trader A's total earnings S can be calculated at $500. The sale of the 100 shares of stock at a strike price of $50 to Trader B = $5,000 (P). The purchase of 100 shares of stock at $40 = $4,000 (Q). The put option premium paid to Trader B for buying the contract of 100 shares at $5 per share, excluding commissions = $500 (R)). Thus
S = (PQ) − R = ($5,000 − $4,000) − $500 = $500

A put option is said to have intrinsic value when the underlying instrument has a spot price (S) below the option's strike price (K). Upon exercise, a put option is valued at K-S if it is "in-the-money", otherwise its value is zero. Prior to exercise, an option has time value apart from its intrinsic value. The following factors reduce the time value of a put option: shortening of the time to expire, decrease in the volatility of the underlying, and increase of interest rates. Option pricing is a central problem of financial mathematics.

See also

Options

Related Research Articles

<span class="mw-page-title-main">Call option</span> Contract giving a buyer the right to buy a security from the seller at a set price

In finance, a call option, often simply labeled a "call", is a contract between the buyer and the seller of the call option to exchange a security at a set price. The buyer of the call option has the right, but not the obligation, to buy an agreed quantity of a particular commodity or financial instrument from the seller of the option at or before a certain time for a certain price. This effectively gives the owner a long position in the given asset. The seller is obliged to sell the commodity or financial instrument to the buyer if the buyer so decides. This effectively gives the seller a short position in the given asset. The buyer pays a fee for this right. The term "call" comes from the fact that the owner has the right to "call the stock away" from the seller.

<span class="mw-page-title-main">Warrant (finance)</span> Security that entitles the holder to buy stock

In finance, a warrant is a security that entitles the holder to buy or sell stock, typically the stock of the issuing company, at a fixed price called the exercise price.

In finance, a straddle strategy involves two transactions in options on the same underlying, with opposite positions. One holds long risk, the other short. As a result, it involves the purchase or sale of particular option derivatives that allow the holder to profit based on how much the price of the underlying security moves, regardless of the direction of price movement.

In finance, the style or family of an option is the class into which the option falls, usually defined by the dates on which the option may be exercised. The vast majority of options are either European or American (style) options. These options—as well as others where the payoff is calculated similarly—are referred to as "vanilla options". Options where the payoff is calculated differently are categorized as "exotic options". Exotic options can pose challenging problems in valuation and hedging.

In finance, a futures contract is a standardized legal contract to buy or sell something at a predetermined price for delivery at a specified time in the future, between parties not yet known to each other. The asset transacted is usually a commodity or financial instrument. The predetermined price of the contract is known as the forward price. The specified time in the future when delivery and payment occur is known as the delivery date. Because it derives its value from the value of the underlying asset, a futures contract is a derivative.

In finance, the time value (TV) of an option is the premium a rational investor would pay over its current exercise value, based on the probability it will increase in value before expiry. For an American option this value is always greater than zero in a fair market, thus an option is always worth more than its current exercise value. As an option can be thought of as 'price insurance', TV can be thought of as the risk premium the option seller charges the buyer—the higher the expected risk, the higher the premium. Conversely, TV can be thought of as the price an investor is willing to pay for potential upside.

In finance, the intrinsic value of an asset or security is its value as calculated with regard to an inherent, objective measure. A distinction, is re the asset's price, which is determined relative to other similar assets. Note, then, that the intrinsic approach to valuation may be somewhat simplified, in that it ignores elements other than the measure in question.

In finance, a price (premium) is paid or received for purchasing or selling options. This article discusses the calculation of this premium in general. For further detail, see: Mathematical finance § Derivatives pricing: the Q world for discussion of the mathematics; Financial engineering for the implementation; as well as Financial modeling § Quantitative finance generally.

The owner of an option contract has the right to exercise it, and thus require that the financial transaction specified by the contract is to be carried out immediately between the two parties, whereupon the option contract is terminated. When exercising a call option, the owner of the option purchases the underlying shares at the strike price from the option seller, while for a put option, the owner of the option sells the underlying to the option seller, again at the strike price.

In finance, a collar is an option strategy that limits the range of possible positive or negative returns on an underlying to a specific range. A collar strategy is used as one of the ways to hedge against possible losses and it represents long put options financed with short call options. The collar combines the strategies of the protective put and the covered call.

In finance, a calendar spread is a spread trade involving the simultaneous purchase of futures or options expiring on a particular date and the sale of the same instrument expiring on another date. These individual purchases, known as the legs of the spread, vary only in expiration date; they are based on the same underlying market and strike price.

In options trading, a bull spread is a bullish, vertical spread options strategy that is designed to profit from a moderate rise in the price of the underlying security.

In options trading, a bear spread is a bearish, vertical spread options strategy that can be used when the options trader is moderately bearish on the underlying security.

<span class="mw-page-title-main">Naked option</span> Investment strategy

A naked option or uncovered option is an options strategy where the options contract writer does not hold the underlying security position to cover the contract in case of assignment. Nor does the seller hold any option of the same class on the same underlying security that could protect against potential losses. A naked option involving a "call" is called a "naked call" or "uncovered call", while one involving a "put" is a "naked put" or "uncovered put".

In finance an iron butterfly, also known as the ironfly, is the name of an advanced, neutral-outlook, options trading strategy that involves buying and holding four different options at three different strike prices. It is a limited-risk, limited-profit trading strategy that is structured for a larger probability of earning smaller limited profit when the underlying stock is perceived to have a low volatility.

Option strategies are the simultaneous, and often mixed, buying or selling of one or more options that differ in one or more of the options' variables. Call options, simply known as Calls, give the buyer a right to buy a particular stock at that option's strike price. Opposite to that are Put options, simply known as Puts, which give the buyer the right to sell a particular stock at the option's strike price. This is often done to gain exposure to a specific type of opportunity or risk while eliminating other risks as part of a trading strategy. A very straightforward strategy might simply be the buying or selling of a single option; however, option strategies often refer to a combination of simultaneous buying and or selling of options.

The backspread is the converse strategy to the ratio spread and is also known as reverse ratio spread. Using calls, a bullish strategy known as the call backspread can be constructed and with puts, a strategy known as the put backspread can be constructed.

Pin risk occurs when the market price of the underlier of an option contract at the time of the contract's expiration is close to the option's strike price. In this situation, the underlier is said to have pinned. The risk to the writer (seller) of the option is that they cannot predict with certainty whether the option will be exercised or not. So the writer cannot hedge their position precisely and may end up with a loss or gain. There is a chance that the price of the underlier may move adversely, resulting in an unanticipated loss to the writer. In other words, an option position may result in a large, undesired risky position in the underlier immediately after expiration, regardless of the actions of the writer.

In finance, an option is a contract which conveys to its owner, the holder, the right, but not the obligation, to buy or sell a specific quantity of an underlying asset or instrument at a specified strike price on or before a specified date, depending on the style of the option. Options are typically acquired by purchase, as a form of compensation, or as part of a complex financial transaction. Thus, they are also a form of asset and have a valuation that may depend on a complex relationship between underlying asset price, time until expiration, market volatility, the risk-free rate of interest, and the strike price of the option. Options may be traded between private parties in over-the-counter (OTC) transactions, or they may be exchange-traded in live, public markets in the form of standardized contracts.

In finance, a credit spread, or net credit spread is an options strategy that involves a purchase of one option and a sale of another option in the same class and expiration but different strike prices. It is designed to make a profit when the spreads between the two options narrows.

References

  1. Matthias Burghardt; Marcel Czink; Ryan Riordan (29 February 2008). "Retail Investor Sentiment and the Stock Market". SSRN   1100038. page 15 | 4.2.3 Positive and negative sentiment