What does it mean when "Adoption of MBIT processes" is listed as a feature of a component?
MBIT is a process developed in the early 1980s, quoting from some sanyo document (SY204A):

MBIT : Multi-base island transistor
MBIT transistors are composed of a large number of
island-like bases and emitters. As the MBIT structure
is an aggregate of &quot;unit transistors&quot;, the emitter
region is sub-divided and its total area and total
peripheral length are increased. This means that
these transistors can operate at higher withstand
voltages and larger currents. In addition, they operate
with uniform emitter current density. The distance
between the base electrode and the transistor base
itself is short, reducing the switching time

It is merely a marketing hint as to what kind of process was used to judge how reliable its features might be (if you know details about the process involved).