The Academic Student Employee Unit (BX) is a systemwide bargaining unit (except UCSF) comprised of graduate teaching assistants, readers, tutors and other instructional assistants who work in support of faculty and lecturers. The unit, which includes a total of about 12,500* graduate students, is represented by the United Auto Workers (UAW).
Campus by campus populations of the BX unit follow (numbers are approximate):
| Location | Headcount |
| Berkeley | 2,879 |
| Davis | 1,576 |
| Irvine | 1,457 |
| Los Angeles | 1,982 |
| Merced | 145 |
| Riverside | 1,047 |
| Santa Barbara | 1,129 |
| Santa Cruz | 626 |
| San Diego | 1,653 |
| Total | 12,494 |
*FTP Data, November 2008
