Sometime in the early part of 2009, after getting the go-signal from its Board of Trustees to explore the possibility of opening up a College or School of Law, an AD HOC Committee was formed by the University President. Principally, it was to gather information and come up with a report on the possibility of opening up a College or School of Law in the University.
On the recommendation of the AD HOC Committee, the Board of Trustees passed BOT RESOLUTION NO. 2010:14 on February 27, 2010, approving the opening of the College of Law.
Because there was a moratorium on the opening of new schools of law, AdZU decided to open a law school in consortium with Xavier University –Ateneo de Cagayan, Cagayan de Oro City. On March 23, 2011, Xavier University –Ateneo de Cagayan, Cagayan de Oro City, applied for authority to open and operate a branch in Zamboanga City with Ateneo de Zamboanga University as its venue.
On May 18, 2011, a certificate of authority to establish a branch of law school in Ateneo de Zamboanga University was granted to the Xavier University – Ateneo de Cagayan College of Law, with a One-Dean-One-Curriculum policy through Government Permit No.28 series of 2011. The authority further provided that the school shall be named Xavier University College of Law – Zamboanga.
In June 2011, the College of Law in AdZU commenced operating as Xavier University College of Law – Zamboanga. It continued to operate as such for School Years 2011-2012, 2012-2013 and 2013-2014.
On Dec. 4, 2013, AdZU re-instated its application. After an inspection and interview conducted by the Legal Education Board Members, Ateneo de Zamboanga University (AdZU) was granted the permit to open a law school through an order dated January 13, 2014.
On May 19, 2022, the College of Law was renamed the Rosendo U Castillo Jr College of Law in honor to its late founding dean, Dean Rosendo U. Castillo, Jr. The move was made to commemorate the memory and contributions of the late Dean to the University and to serve as inspiration for future generations of Ignatian lawyers.
