• March 23, 2010: President Barack Obama signs the Patient Protection and Affordable Care Act into law.
• March 23, 2010: Florida and several other states file a lawsuit in federal court challenging the constitutionality of the Affordable Care Act.
• November 2010: Voters passed State Question 756, which sought to prevent many aspects of the Affordable Care Act from taking effect in Oklahoma.
• January 2011: Oklahoma Attorney General Scott Pruitt files a lawsuit in federal court challenging the constitutionality of the Affordable Care Act. That lawsuit is put on hold by Judge Ronald White pending a decision from the U.S. Supreme Court on the challenge coming from Florida.
• February 2011: Oklahoma is awarded a $54.6 million “early innovator” grant to set up a health insurance exchange. The application was written by Gov. Brad Henry's office but approved by Gov. Mary Fallin's transition team before it was submitted.
• April 2011: Fallin announces the state will not accept a $54.6 million grant for setting up a system where Oklahomans could shop for health insurance.
• June 2012: Supreme Court rules much of the Affordable Care Act is constitutional, including the mandate that individuals purchase health insurance, the mandated health care exchanges, but it allows states to decide on the Medicaid
• September: Pruitt renews Oklahoma's legal challenge to the act in federal court in Muskogee.
• October: GOP leadership in Oklahoma announces they will wait for results of the presidential election to make a decision on the health care exchange and Medicaid expansion, with the hope that Mitt Romney will be elected and repeal the law.
• Nov. 6: Romney is defeated by Obama.
• Nov. 19: Fallin announces the state will not set up a health care exchange or expand Medicaid.