The most recent high-precision data on spin observables Σ, T , P ′ , E, F and H reported by the CLAS Collaboration together with the previous data on differential cross sections and spin-densitymatrix elements reported by the CLAS, A2, GRAAL, SAPHIR and CBELSA/TAPS Collaborations for the reaction γp → ωp are analyzed within an effective Lagrangian approach. The reaction amplitude is constructed by considering the t-channel π and η exchanges, the s-channel nucleon and nucleon resonances exchanges, the u-channel nucleon exchange and the generalized contact current, with the last one being formulated to ensure that the full photoproduction amplitudes satisfy the generalized Ward-Takahashi identity and thus are fully gauge invariant. It is shown that all the available CLAS data can be satisfactorily described by considering the N (1520)3/2 − , N (1700)3/2 − , N (1720)3/2 + , N (1860)5/2 + , N (1875)3/2 − , N (1895)1/2 − and N (2060)5/2 − exchanges in the s channel. The parameters of these resonances are extracted and compared with those quoted by PDG.

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