  We derive a sum rule which shows how to extend LEP limits on the masses of
the lightest CP-even and CP-odd Higgs bosons of a CP-conserving
two-Higgs-doublet model to any two Higgs bosons of a general CP-violating
two-Higgs-doublet model. We generalize the analysis to a Higgs sector
consisting of an arbitrary number of Higgs doublets and singlets, giving
explicit limits for the CP-conserving and CP-violating two-doublet plus
one-singlet Higgs sectors.
