Law Of One Price

Dictionary Says

Definition of 'Law Of One Price'

The theory that the price of a given security, commodity or asset will have the same price when exchange rates are taken into consideration. The law of one price is another way of stating the concept of purchasing power parity.
Investopedia Says

Investopedia explains 'Law Of One Price'

The law of one price exists due to arbitrage opportunities. If the price of a security, commodity or asset is different in two different markets, then an arbitrageur will purchase the asset in the cheaper market and sell it where prices are higher.

When the purchasing power parity doesn't hold, arbitrage profits will persist until the price converges across markets.

Related Definitions

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  • Exchange Rate

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    • Arbitrage

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    • Uncovered Interest Rate Parity - UIP

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    • Gresham's Law

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