  The origin of a family-independent "extra U(1)", discovered by Barr, Bednarz,
and Benesh and independently by Ma, and whose phenomenology has recently been
studied by Ma and Roy, is discussed. Even though it satisfies anomaly
constraints in a highly economical way, with just a single extra triplet of
leptons per family, this extra U(1) cannot come from four-dimensional grand
unification. However, it is shown here that it can come from a Pati-Salam
scheme with an extra U(1), which explains the otherwise surprising cancellation
of anomalies.
