99-year lease

A 99-year lease was, under historic common law, the longest possible term of a lease of real property. It is no longer the law in most common law jurisdictions today, yet 99-year leases continue to be common as a matter of business practice and conventional wisdom.

Under the traditional American common law doctrine, the 99-year term was not literal, but merely an arbitrary time span beyond the life expectancy of any possible lessee or lessor.

William Blackstone states that a lease was formerly limited to 40 years, although much longer leases (for 300 years, or 1000 years) were in use by the time of Edward III. The 40-year limit was based on the unreliable text "The Mirror of Justices" (book 2, chapter 27).

In the law of several US states, a 99-year lease will always be the longest possible contract for realty by statute, but many have enacted shorter terms and some allow infinite terms.

The 99-year lease concept has been more common under the civil law regimes when it comes to concessions of territory: most concessions last for 99 years.

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