The NFL Concussion timeline reported by CNN on August 2016:

• 1994 – the Mild Traumatic Brain Injury Committee is created by the NFL Commissioner Paul Tagliabue
• 2002 – Dr. Bennet Omalu, co-founder of the Brain Injury Research Institute, identifies chronic traumatic encephalopathy (CTE) for the first time in American football players from a post-mortem exam of the brain of former Pittsburgh Steelers’ center Mike Webster, who committed suicide.
• January 2005 – the NFL’s Mild Traumatic Brain Injury Committee concludes that there is no significant risk of a second injury within the same game or season upon returning to play after sustaining a concussion.
• 2005 and 2006 – Dr. Omalu identifies chronic traumatic encephalopathy (CTE) in the brains of former American football players who had committed suicide.
• June 2007 – the NFL holds a medical conference on concussions.
• August 2007 – the NFL creates new concussion guidelines
• October 2009 – the NFL Commissioner Roger Goodell defends the League’s policy regarding concussions at the House Judiciary Committee hearing on Legal Issues Relating to Football Head Injuries
• January 2010 – the NFL’s Mild Traumatic Brain Injury Committee denies a link between repeat head impacts and long-term brain damage at the second House Judiciary Committee hearing on Legal Issues Relating to Football Head Injuries
• February 2011 – another deceased NFL player shows signs of having chronic traumatic encephalopathy (CTE) after committing suicide.
• June 2012 – a lawsuit combining more than 80 concussion-related lawsuits of more than 2,000 NFL players is filed in federal court in Philadelphia, accusing the NFL of negligence and failing to notify players of the link between concussions and brain injuries, in Multi-District Litigation Case No. 2323.
• August 2012 – the NFL files motion to dismiss the concussion related lawsuits filed by former players.
• September 2012 – the Foundation for the National Institutes of Health announces the NFL has committed to donating $30 million to support research on medical conditions prominent in athletes.
• August 2013 – NFL agrees to pay $765 million dollars to former NFL players who developed “brain disorders” due to concussions caused by in-play collisions, plus an additional $75 million for medical exams and another $10 million for medical research.
• January 2014 – A federal judge declines to approve a proposed $760 million settlement of claims arising from concussions suffered by NFL players, saying she didn’t think it was enough money.
• May 2014 – fifteen former NFL players sue the NFL over concussions, claiming the NFL knew for years of the link between concussions and long-term health problems.
• April 2015 – A federal judge passes final approval to a class-action lawsuit settlement between the NFL and thousands of former players, which provides up to $5 million per retired player for serious medical conditions associated with repeated head trauma.
• March 2016 – a senior NFL official publicly acknowledges a connection between football and CTE for the first time.
• July 2016 – the NFL and NFL Players’ Association (NFLPA) implement a new policy to enforce concussion protocol. Teams violating the policy are subject to discipline, through fines or losing upcoming draft picks.