We report on the thickness dependence of the superconducting characteristics including critical currentIc, critical current densityJc, transition temperatureTc, irreversibility fieldHirr, bulk pinning forceplot Fp(H), and normalstate resistivity curve ρ(T) measured after successive ion milling of∼1 µm thickhigh-Ic YBa2Cu3O7−x films made by an ex situ metal–organic deposition process on Ni–W rolling-assisted biaxially texturedsubstrates (RABiTSTM). In contrast to many recent data, mostly on in situ pulsedlaser deposition (PLD) films, which show strong depression ofJc with increasingfilm thickness t, our films exhibit only a weak dependence ofJc on t. The two better textured samples had full cross-section averageJc,avg (77 K, 0 T)∼4 MA cm−2 near the bufferlayer interface and ∼3 MA cm−2 at full thickness, despite significant current blocking due to∼30% porosity in the film. Taking account of the thickness dependence of the porosity, we estimate thatthe local, vortex-pinning current density is essentially independent of thickness, while accountingfor the additional current-blocking effects of grain boundaries leads to local, vortex-pinningJc values wellabove 5 MA cm−2. Suchhigh local Jc values are produced by strong three-dimensional vortex pinning which subdivides vortexlines into weakly coupled segments much shorter than the film thickness.