Here's a look at BALCO, the lab that provided steroids to several professional athletes, including baseball player Barry Bonds and track and field star Marion Jones.
The BALCO scandal began as two separate, independent investigations: one by federal agents in California looking into BALCO, and one by investigators for the U.S. Anti-Doping Agency working on a tip from an anonymous source.
BALCO stands for Bay Area Laboratory Co-Operative.
August 2002 - Federal agents begin investigating BALCO, a California lab suspected of selling banned performance enhancing drugs to athletes.
June 2003 - THE USADA receives an anonymous tip that an undetectable, designer steroid is being distributed by Victor Conte, founder of BALCO. The tipster sends the USADA a syringe filled with the steroid. The tipster is later identified as Trevor Graham, the former coach of runners Tim Montgomery and Marion Jones.
September 2003 - BALCO offices are raided by agents of the Internal Revenue Service and a San Mateo County narcotics task force. Also raided is the home of Greg Anderson, a personal trainer for Barry Bonds.
October 16, 2003 - The USADA announces it has uncovered a doping "conspiracy" involving previously undetectable steroids used by track and field athletes.
October 23, 2003 - A grand jury investigation into BALCO begins. Dozens of high profile athletes are subpoenaed to testify during the investigation.
2004 - Marion Jones files a $25 million defamation lawsuit against Victor Conte accusing him of trying to "destroy her career and reputation" when he said he supplied her with performance enhancing drugs. The lawsuit is settled out of court for an undisclosed amount.
February 12, 2004 - Victor Conte, BALCO executive James Valente, trainer Greg Anderson, and track coach Remi Korchemny are indicted on charges of money laundering, fraud and possession with intent to distribute steroids. The following day all of the defendants plead not guilty.
December 2, 2004 - The San Francisco Chronicle begins revealing secret grand jury testimony from several major baseball players, during which some of the baseball players admitted to steroid use. Barry Bonds testified that he used a substance given to him by trainer Greg Anderson, but that he (Bonds) did not know they were steroids.
December 3, 2004 - U.S. Attorney Kevin Ryan requests a formal investigation into who is leaking grand jury testimony to reporters.
July 15, 2005 - Victor Conte and Greg Anderson plead guilty to steroid distribution and money laundering. James Valente pleads guilty to steroid distribution.
July 29, 2005 - Track coach Remi Korchemny pleads guilty to reduced charges. He is later sentenced to one year of probation.
October 18, 2005 - Victor Conte is sentenced to four months in prison and four months house arrest. Greg Anderson is sentenced to three months in prison and three months house arrest. James Valente receives probation.
February 2007 - Troy Ellerman, former attorney for Victor Conte, admits to showing grand jury testimony to a San Francisco Chronicle reporter. Ellerman pleads guilty to four felonies, including contempt of court and obstruction of justice.
July 12, 2007 - Ellerman is sentenced to two-and-a-half years in prison.
October 5, 2007 - Marion Jones pleads guilty to charges of lying to a federal agent in 2003 about her steroid use.
November 15, 2007 - A federal jury indicts Barry Bonds on perjury and obstruction of justice charges. The indictment is in connection to an investigation of the use of steroids in major league baseball.
April 13, 2011 - Bonds is convicted of one count of obstruction of justice. A mistrial is declared on three counts of perjury after jurors report they cannot reach an agreement.
December 16, 2011 - Bonds is sentenced to 30 days of house arrest and two years of probation for obstruction of justice.
May 3, 2012 - Bonds files a brief with the Ninth U.S. Circuit Court of Appeals urging the court to overturn his obstruction of justice conviction.
September 13, 2013 - The Ninth U.S. Circuit Court of Appeals upholds Bonds' conviction.
Athletes involved (not comprehensive):
Major League Baseball
Barry Bonds and Gary Sheffield: Testified before the federal grand jury that they unknowingly took steroids given to them by Greg Anderson.
Jason Giambi, Jeremy Giambi, Armando Rios, Benito Santiago, Bobby Estalella: Testified before the federal grand jury that they used steroids provided to them by Greg Anderson:
Track & Field
Marion Jones: Admitted that she used steroids before the 2000 Summer Olympics and lied to federal prosecutors about it. She was sentenced to six months in prison and two years of probation.
Regina Jacobs: Tested positive and suspended from competition for four years.
Alvin Harrison and Michelle Collins - Suspended from competition for four years.
Kevin Toth, John McEwen, Dwain Chambers, Calvin Harrison, Melissa Price: Tested positive and suspended from competition for two years.
Tim Montgomery: Testified before the federal grand jury that he unknowingly used steroids provided to him by Victor Conte. Suspended from competition for two years.
Chryste Gaines and Kelli White: Suspended from competition for two years.
Sandra Glover, Christopher Phillips, Eric Thomas: Tested positive and given a warning
Bill Romanowski - Tested positive, but had already retired.
Barret Robbins, Dana Stubblefield, and Chris Cooper - Tested positive. Fined by the NFL.
Shane Mosley - Admitted he unknowingly took steroids provided by BALCO.