A formulation of the linear $sigma$ model with derivative interactions is studied. The classical theory is on-shell equivalent to the $sigma$ model with the standard quartic Higgs potential. The mass of the scalar mode only appears in the quadratic part and not in the interaction vertices, unlike in the ordinary formulation of the theory. Renormalization of the model is discussed. A non power-counting renormalizable extension, obeying the defining functional identities of the theory, is presented. This extension is physically equivalent to the tree-level inclusion of a dimension six effective operator $partial_mu (Phi^dagger Phi) partial^mu (Phi^dagger Phi)$. The resulting UV divergences are arranged in a perturbation series around the power-counting renormalizable theory. The application of the formalism to the Standard Model in the presence of the dimension-six operator $partial_mu (Phi^dagger Phi) partial^mu (Phi^dagger Phi)$ is discussed.
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