<P> After each stage, four riders are tested: the overall leader, the stage winner, and two riders at random . In addition, every rider is tested before the first day's stage, normally a short time - trial . Most teams are tested in their entirety at some point during the three - week race . Additional testing may take place during the off - season, and riders are expected to keep their national cycling federation informed of their whereabouts so they can be located . Many teams have their own drug testing programs to keep the team name clean . Teams, such as Quick - Step, have pulled riders before they compete in major competitions . Tom Boonen was pulled for cocaine before the 2008 Tour de France . </P> <P> 14 of the 25 most recent winners (56%) have either been tested positive or have confessed to have used doping . Together with those tested positive, but never sanctioned, 68% of the winners evidently used doping as detailed in the table below . </P> <Table> <Tr> <Th> Years </Th> <Th> Name </Th> <Th> Status </Th> <Th> Details </Th> </Tr> <Tr> <Td> 2014 </Td> <Td> Vincenzo Nibali </Td> <Td> Never tested positive </Td> <Td> </Td> </Tr> <Tr> <Td> 2013 2015 2016 2017 </Td> <Td> Chris Froome </Td> <Td> Never tested positive </Td> <Td> </Td> </Tr> <Tr> <Td> 2012 </Td> <Td> Bradley Wiggins </Td> <Td> Never tested positive </Td> <Td> </Td> </Tr> <Tr> <Td> 2011 </Td> <Td> Cadel Evans </Td> <Td> Never tested positive </Td> <Td> </Td> </Tr> <Tr> <Td> </Td> <Td> Andy Schleck </Td> <Td> Never tested positive </Td> <Td> Named as winner after Contador disqualified . </Td> </Tr> <Tr> <Td> 2007 2009 </Td> <Td> Alberto Contador </Td> <Td> Tested positive Banned for two years </Td> <Td> Named in Operación Puerto doping case, but later declared clean . Tested positive during 2010 Tour de France for the banned stimulant clenbuterol . Suspended for two years . </Td> </Tr> <Tr> <Td> 2008 </Td> <Td> Carlos Sastre </Td> <Td> Never tested positive </Td> <Td> </Td> </Tr> <Tr> <Td> 2006 </Td> <Td> Óscar Pereiro </Td> <Td> Never tested positive </Td> <Td> Named as winner after Landis disqualified . Took salbutamol in 2006, but had a Therapeutic Use Exemption (TUE) for the substance as part of asthma treatment . </Td> </Tr> <Tr> <Td> Floyd Landis </Td> <Td> Tested positive Banned for two years </Td> <Td> Tested positive for high testosterone to epitestosterone ratio; </Td> </Tr> <Tr> <Td> 1999--2005 </Td> <Td_colspan="3"> No winner after Armstrong disqualified . Six of the seven overall runners - up to Armstrong (all except Joseba Beloki in 2002) have either admitted to or been found guilty of doping . </Td> </Tr> <Tr> <Td> Lance Armstrong </Td> <Td> Banned for life . Retroactively stripped of all titles since August 1998 . Confessed doping use </Td> <Td> Tested positive for glucocorticosteroid hormone without prescription given in advance . <P> Associated with Michele Ferrari, who is suspected of prescribing doping agents . Allegations by former assistant for Androstenine use . Alleged EPO use in 1999 Tour de France . According to court testimony by former teammate, Frankie Andreu, Armstrong admitted to doping to his doctor when in hospital for cancer treatment . Floyd Landis accused Armstrong of doping in 2002 and 2003, and claimed that U.S. Postal team director Johan Bruyneel had bribed former UCI president Hein Verbruggen to keep quiet about a positive Armstrong test in 2002 . Landis also maintains that he witnessed Armstrong receiving multiple blood transfusions, and dispensing testosterone patches to his teammates on the United States Postal Service Team . Former teammate Tyler Hamilton accused Armstrong of doping with testimony to a federal grand jury during an investigation of Armstrong . Hamilton implicated that Armstrong had used EPO on the TV news show 60 Minutes . Implicated in a massive doping scheme by findings by USADA in 2012 . Consequently, banned for life and stripped of all career titles since August 1998 . </P> <P> Admitted to doping at all seven of his victorious Tours in a 2013 interview with Oprah Winfrey . </P> </Td> </Tr> <Tr> <Td> 1998 </Td> <Td> Marco Pantani </Td> <Td> Never tested positive Banned for six months </Td> <Td> Failed a blood test in 1999 Giro d'Italia . Insulin found in his hotel room in the 2001 Giro d'Italia, but later declared clean "for not having committed any infraction ." Nonetheless, the UCI confirmed the suspension . </Td> </Tr> <Tr> <Td> 1997 </Td> <Td> Jan Ullrich </Td> <Td> Tested positive Banned from the 2006 Tour Retroactively stripped of titles 2005--2007 . Confessed doping use </Td> <Td> Tested positive for amphetamines (off season, not taken for athletic performance gain) <P> Involved in the Operacion Puerto case . DNA subsequently linked to blood bag discovered during Puerto investigation </P> <P> Admitted to doping in a 2013 interview with the German magazine Focus . </P> </Td> </Tr> <Tr> <Td> </Td> <Td> Bjarne Riis </Td> <Td> Never tested positive Confessed doping use </Td> <Td> Confessed having used EPO in 1996 </Td> </Tr> <Tr> <Td> 1991--1995 </Td> <Td> Miguel Indurain </Td> <Td> Never tested positive </Td> <Td> Tested positive for salbutamol in 1994, however both the IOC and UCI allowed Indurain, and asthma sufferers to use Salbutomol at the time . </Td> </Tr> <Tr> <Td> 1986 1989--1990 </Td> <Td> Greg LeMond </Td> <Td> Never tested positive </Td> <Td> </Td> </Tr> <Tr> <Td> 1988 </Td> <Td> Pedro Delgado </Td> <Td> Never tested positive </Td> <Td> Tested positive for probenecid, a masking agent for anabolic steroids in the 1988 Tour de France but, although banned by the IOC, it was not on the UCI list of banned substances at the time . </Td> </Tr> <Tr> <Td> </Td> <Td> Stephen Roche </Td> <Td> Never tested positive </Td> <Td> Accused of taking EPO in 1993 as part of an investigation in Italy into the practices of Francesco Conconi </Td> </Tr> <Tr> <Td> 1978--1979 1981--1982 1985 </Td> <Td> Bernard Hinault </Td> <Td> Never tested positive </Td> <Td> </Td> </Tr> <Tr> <Td> 1983--1984 </Td> <Td> Laurent Fignon </Td> <Td> Tested positive </Td> <Td> In 1989 Fignon tested positive after a team time trial tested positive for amphetamines at the Grand Prix de la Liberation in Eindhoven on 17 September 1989 . </Td> </Tr> <Tr> <Td> 1980 </Td> <Td> Joop Zoetemelk </Td> <Td> Tested positive </Td> <Td> Tested positive in the 1977 (pemoline), 1979 (steroids) and 1983 Tour de France (nandrolon, although that was retracted later). Admitted a blood transfusion on TV interviews right after winning the 10th (and 9th) stage of the 1976 Tour de France, as in that era it was seen as just medical aid . </Td> </Tr> <Tr> <Td> 1977 </Td> <Td> Bernard Thévenet </Td> <Td> Never tested positive Confessed doping use </Td> <Td> Admitted using steroids in the 1975 and 1977 Tour </Td> </Tr> <Tr> <Td> 1976 </Td> <Td> Lucien Van Impe </Td> <Td> Never tested positive </Td> <Td> </Td> </Tr> <Tr> <Td> 1969--1972 </Td> <Td> Eddy Merckx </Td> <Td> Tested positive </Td> <Td> Merckx has tested positive three times, but never at the Tour de France . He was expelled from the 1969 Giro d'Italia after testing positive for Reactivan . <P> He tested positive for Mucantil after winning the 1973 Giro di Lombardia . The drug was later taken off the banned list . In the 1977 Flèche Wallonne, Merckx tested positive for Stimul (pemoline), along with Freddy Maertens and Michel Pollentier . </P> </Td> </Tr> <Tr> <Td> 1973 </Td> <Td> Luis Ocaña </Td> <Td> Tested positive </Td> <Td> Tested positive in the 1977 Tour de France (pemoline) 18th stage . </Td> </Tr> <Tr> <Td> 1968 </Td> <Td> Jan Janssen </Td> <Td> Never tested positive </Td> <Td> </Td> </Tr> <Tr> <Td> 1967 </Td> <Td> Roger Pingeon </Td> <Td> Never tested positive </Td> <Td> </Td> </Tr> <Tr> <Td> 1966 </Td> <Td> Lucien Aimar </Td> <Td> Tested positive Banned for one month </Td> <Td> Missed the 1969 Vuelta a España due to a one - month doping ban . </Td> </Tr> <Tr> <Td> 1965 </Td> <Td> Felice Gimondi </Td> <Td> Tested positive </Td> <Td> Tested positive in the 1968 Giro and 1975 Tour . </Td> </Tr> <Tr> <Td> 1957 1961--1964 </Td> <Td> Jacques Anquetil </Td> <Td> Confessed doping use </Td> <Td> Debated with French government minister on television, saying "Leave me in peace; everybody takes dope ." After winning Liège--Bastogne--Liège in 1966, was temporarily disqualified after refusing a drug test, saying he had already been to the toilet . He was later reinstated after he engaged a lawyer as the case was never heard . </Td> </Tr> </Table> <Tr> <Th> Years </Th> <Th> Name </Th> <Th> Status </Th> <Th> Details </Th> </Tr>

List of tour de france winners stripped of title