  This paper describes an issue that arises when inverting elements of the
homotopy groups of an equivariant commutative ring. Equivariant commutative
rings possess an enhanced multiplicative structure arising from the presence of
"indexed products" (products indexed by a set with a non-trivial action of the
group). The formation of the "multiplicative closure" of a set must be altered
in order to accomodate this structure, and the result of localizing an
equivariant commutative ring can have an unexpected homotopy type.
