In the American education system, the Common Core is defined as
A set of high-quality academic standards in mathematics and English language arts/literacy (ELA). These learning goals outline what a student should know and be able to do at the end of each grade.
The Common Core was established in 2009 to act as a framework for establishing a singular academic standard throughout the United States.
The Insider Threat Common Core (ITCC) is an open source framework and maturity model for the development, implementation, and enhancement of corporate security programs focused on insider threat, insider risk, data loss prevention, or other related data protection / threat management efforts. As such, I define the ITCC as
A set of usable processes, methodologies, and program standards for implementing high-quality insider threat and data protection programs.