Higgs Boson Interference in $\gamma \gamma \to W^{+}{W}^{-}$

We study interference effects between resonant and nonresonant amplitudes for the $\gamma \gamma \to W^{+}{W}^{-}$ process at a backscattered photon-photon collider. We show that a Higgs boson with $M_H$ > 200 GeV is manifest as a resonant dip in the $W^{+}{W}^{-}$ invariant mass spectrum and we investigate its statistical significance.