  Given a bipartite graph $H=(V=V_A\cup V_B,E)$ in which any vertex in $V_A$
(resp.~$V_B$) has degree at most $D_A$ (resp.~$D_B$), suppose there is a
partition of $V$ that is a refinement of the bipartition $V_A\cup V_B$ such
that the parts in $V_A$ (resp.~$V_B$) have size at least $k_A$ (resp.~$k_B$).
We prove that the condition $D_A/k_B+D_B/k_A\le 1$ is sufficient for the
existence of an independent set of vertices of $H$ that is simultaneously
transversal to the partition, and show moreover that this condition is sharp.
This result is a bipartite refinement of two well-known results on independent
transversals, one due to the second author and the other due to Szab\'o and
Tardos.
