(Reuters) - The U.S. Supreme Court on Monday handed a victory to abortion rights advocates, striking down a Texas law imposing strict regulations on abortion doctors and facilities. Following is a timeline of that challenge. July 2013 - The Republican-led Texas legislature passes and Republican Governor Rick Perry signs the law known as H.B. 2, putting new requirements on abortion providers. State officials say the law is intended to ensure the health and safety of women. September 2013 – Before the law is enforced, Planned Parenthood and other abortion providers challenge the measure. They assert that certain provisions, including one related to doctors’ “admitting privileges” - a type of formal affiliation - at a hospital within 30 miles (48 km) of an abortion clinic, are aimed at decreasing the abortion availability in the state. October 2013 – A U.S. district judge sides largely with the challengers, blocking the admitting privileges provision. March 2014 - The New Orleans-based U.S. Court of Appeals for the 5th Circuit, a regional federal appeals court covering Texas, Louisiana and Mississippi, reverses the lower court and permits much of the law to take effect.  April 2014 - Whole Woman’s Health and other abortion providers bring a new complaint against Texas, citing the effect of the law’s implementation and the number of clinics that have closed. The challengers focus on the admitting-privileges requirement and regulations governing clinic facility standards. August 2014 – A U.S. district court judge declares the admitting privileges and clinic requirements an unconstitutional burden on women’s access to abortion. October 2014 - The U.S. Court of Appeals for the 5th Circuit intervenes to allow implementation of both new regulations, but the U.S. Supreme Court blocks part of the order so that the mandate that clinics meet hospital-grade standards does not go into effect. June 2015 - After considering the full merits of the challenge, the U.S. Court of Appeals for the 5th Circuit reverses the district judge’s decision, finding the judge should have deferred to the legislature’s stated health and safety goals. The appeals court also says most of the lawsuit should have been barred because the legal issues it raises already were addressed in the case filed by Planned Parenthood. June 2015 - The U.S. Supreme Court by a 5-4 vote puts a temporary hold on the 5th Circuit’s ruling while the justices consider whether to hear the challengers’ appeal. That action blocks the provision regarding hospital-grade standards from taking effect. September 2015 - The abortion providers challenging the Texas restrictions ask the U.S. Supreme Court to hear their appeal of the 5th Circuit’s ruling. November 2015 - The U.S. Supreme Court agrees to hear the challenge by abortion providers to the Texas restrictions. February 2016 - Conservative U.S. Supreme Court Justice Antonin Scalia, a supporter of abortion restrictions, dies at age 79, leaving the court shorthanded and evenly divided with four liberals and four conservatives. March 2016 - The U.S. Supreme Court hears 85 minutes of oral arguments in the case, known as Whole Woman’s Health v. Hellerstedt. The court’s four liberal justices indicate they believe the law intrudes on a woman’s constitutional right to abortion. The four conservative justices express doubts about claims by abortion providers that the law forced numerous clinics to shut down. June 2016 - The U.S. Supreme Court strikes down the Texas law, finding that it places an undue burden on women exercising their right under the U.S. Constitution to end a pregnancy. The court declares that both provisions of the law - “admitting privileges” and hospital-grade facilities - are unconstitutional. The ruling marks the firmest endorsement of U.S. abortion rights since the 1992 Planned Parenthood of Southeastern Pennsylvania v. Casey ruling. 