  The J\"ulich-Bonn coupled-channel framework is extended to $K^+\Lambda$
photoproduction. The spectrum of nucleon and $\Delta$ resonances is extracted
from simultaneous fits to several pion-induced reactions in addition to pion,
eta and $K^+\Lambda$ photoproduction off the proton. More than 40,000 data
points up to a center-of-mass energy of E$\sim$2.3 GeV including recently
measured double-polarization observables are analyzed. The influence of the
$\gamma p\to K^+\Lambda$ channel on the extracted resonance parameters and the
appearance of states not seen in other channels is investigated. The
J\"ulich-Bonn model includes effective three-body channels and guarantees
unitarity and analyticity, which is a prerequisite for a reliable determination
of the resonance spectrum in terms of poles and residues.
