Martinez v. Regents of the University of California is a landmark class-action civil lawsuit filed in 2005 by Robert Martinez and other U.S. citizen nonresident students challenging California Education Code section 68130.5 (AB 540). The statute grants in-state tuition rates at California public postsecondary institutions to undocumented immigrants who attended a California high school for at least three years and graduated or obtained a GED, provided they register an affidavit stating intent to legalize status. Plaintiffs argued the law was preempted by federal law (8 U.S.C. § 1623(a)), which bars states from providing postsecondary education benefits to undocumented aliens unavailable on the same terms to all U.S. citizens. The Superior Court sustained demurrers without leave to amend; the Third District Court of Appeal affirmed (166 Cal. App. 4th 1121, 2008); the California Supreme Court granted review (S167791) and held 6-1 in 2010 (50 Cal. 4th 1277) that the state law is not expressly preempted and no field or conflict preemption applies, as eligibility turns on high school attendance rather than residence. The U.S. Supreme Court denied certiorari (10-1029, 2011). The decision solidified California's policy providing access to affordable higher education for undocumented students, influencing similar laws nationwide.