Let $(Z_{t})_{t \geq 0}$ be a planar Brownian motion running in some domain W and denote by $\tau _{W}$ the exit time of $Z_{t}$ from W. To establish the finiteness of $\mathbf {E}(\sup _{0\leq t\leq \tau _{W}}|Z_{t}|^{p})$ from the finiteness of $\mathbf {E}(|Z_{\tau _{W}}|^{p})$ for some $p>0$, Burkholder [‘Exit times of Brownian motion, harmonic majorization, and Hardy spaces’, Adv. Math. 26(2) (1977), 182–205] imposed an additional condition on the exit time $\tau _{W}$, namely the finiteness of $\mathbf {E}(\log (\tau _{W}))$. Such a condition is typically difficult to verify, since the law of the exit time is often delicate. In this paper, we revisit Burkholder’s condition and propose an alternative viewpoint. Our approach is purely analytic, weaker and formulated in terms of proper analytic maps rather than exit times themselves. This provides a more flexible framework for further applications.

For n≥2, a hypersurface in the open unit ball Bn in is constructed which satisfies the generalized Blaschke condition and is a uniqueness set for all Hp(Bn) with p>0. If n≥3, the hypersurface can be chosen to have finite area.

Subject classification (Amer. Math. Soc. (MOS) 1970): primary 32 A 10.