  The trilepton nucleon decay modes $p \rightarrow e^+ \nu \nu$ and $p
\rightarrow \mu^+ \nu \nu$ violate $|\Delta (B - L)|$ by two units. Using data
from a 273.4 kiloton year exposure of Super-Kamiokande a search for these
decays yields a fit consistent with no signal. Accordingly, lower limits on the
partial lifetimes of $\tau_{p \rightarrow e^+ \nu \nu} > 1.7 \times 10^{32}$
years and $\tau_{p \rightarrow \mu^+ \nu \nu} > 2.2 \times 10^{32}$ years at a
$90 \% $ confidence level are obtained. These limits can constrain Grand
Unified Theories which allow for such processes.
