Angeles, Santa Cruz, Santa Barbara, Riverside, and Irvine campuses—all of them approving a teaching assistant union. In 2000, union negotiations for all of the campuses were combined into UAW Local 2865, who bargains on behalf of all the campuses. Teaching assistants at the University of California, Merced also joined the union when the campus opened in 2006. Several notable unionization efforts arose at private universities. Although pre-NYU-rulings by the NLRB did not permit graduate students to unionize at private universities, they also did not prohibit universities from recognizing unions. Teaching assistant unions formed at Yale and New York University. To gain bargaining status, the unions went on several strikes and led long union drive campaigns. Throughout the 1990s and early 2000s, Yale graduate students organized a sustained union drive campaign, which remains ongoing. In response to poor pay and working conditions, Yale's graduate students formed Teaching Assistant Solidarity in 1987, which later became the Graduate Employees and Students Organization (GESO) in 1990. Students orchestrated multiple strikes to gain union recognition. GESO orchestrated a one-day walkout in December 1991 and a three-day strike in February 1992. Additionally, Yale graduate students participated in a walkout on April 6, 1995, to demand union recognition. Despite a later 600–120 vote in favor of union representation, the university refused to negotiate a contract. In 1996, teaching assistants at Yale refused to calculate and submit fall semester grades. The administration still refused to recognize the union and the strike eventually ended. A suit was filed by the NLRB on behalf of the striking Yale students claiming Yale's administration violated unfair-labor-practice law; however, a judge later dismissed the suit. GESO participated in a five-day strike along with other unions in Yale University in March 2003 for better wages and pensions and demand for union recognition. However, in a union voting drive the following May, Yale graduate students rejected unionization by a narrow 694–651 margin. In 2000, the National Labor Relations Board reversed their previous rulings on unionization at private universities and permitted graduate assistants at New York University (NYU) to unionize. Later that year, graduate assistants at NYU signed their first and only contract. Since 2000, more than twenty campuses have unionized. In 2001, the University of Massachusetts Boston signed their first contract with teaching and research assistants while Oregon State University won a contract—the second to receive a contract in Oregon. In 2002, Michigan State University