  At sufficiently large proton energies, Glauber multiple-scattering theory
offers good opportunities for describing the final state interactions in
electro-induced proton emission off nuclear targets. A fully unfactorized
relativistic formulation of Glauber multiple-scattering theory is presented.
The effect of truncating the Glauber multiple-scattering series is discussed.
Relativistic effects in the description of the final-state interactions are
found not to exceed the few percent level. Also the frequently adopted
approximation of replacing the wave functions for the individual scattering
nucleons by some average density, is observed to have a minor impact on the
results. Predictions for the separated $^4$He$(e,e'p)$ response functions are
given in quasi-elastic kinematics and a domain corresponding with $1 \leq Q^2
\leq 2$ (GeV)$^2$.
