Might be a number of things, depending on the context you're looking for:
Acronym Definition
MSRC Microsoft Security Response Center
MSRC Major Shared-Resource Center (Army Research Laboratory)
MSRC Marine Spill Response Corporation
MSRC Marine Sciences Research Center
MSRC Mobile Source Air Pollution Reduction Review Committee
MSRC Media Security and Reliability Council
MSRC Magnetic Selective Ride Control
MSRC Materials Science Research Centre (India)
MSRC Master-Subsidiary Relationship Code
MSRC Molecular Sciences Research Center
Those are just some of the acronym definitions I found.