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Put-Call Parity And The Law, Michael S. Knoll

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A common literary theme is the conflict between appearance and reality. That conflict also frequently arises in the law, where it is usually cast as one between substance and form. Another discipline in which the conflict arises is finance, where it appears in the put-call parity theorem. That theorem states that given any three of the four following financial instruments--a riskless zero-coupon bond, a share of stock, a call option on the stock, and a put option on the stock--the fourth instrument can be replicated. Thus, the theorem implies that any financial position containing these assets can be constructed in …