Leonardo da Vinci painted an earlier version of his famed masterpiece `` Mona Lisa , '' claims a private Swiss art foundation dedicated solely to the alternate painting , which it unveiled Thursday . But an expert on da Vinci in Britain says there is evidence that the Renaissance master may not have been behind the picture presented as the `` Earlier Mona Lisa '' but known more commonly as the `` Isleworth Mona Lisa . '' The Mona Lisa Foundation , based in Zurich , offers a wealth of documentation to support its argument that the painting it represents is a predecessor -- from the master 's own hand -- to the world 's most famous portrait hanging in the Louvre Museum in Paris . Martin Kemp , professor emeritus at Oxford University , who has examined the arguments , says the `` reliable primary evidence provides no basis for thinking that there was 'an earlier ' portrait of Lisa del Giocondo . '' Da Vinci 's lost masterpiece may be found . In addition to a 320-page art book titled `` Mona Lisa : Leonardo 's Earlier Version , '' the foundation 's website makes its case using visual widgets of painstaking side-by-side comparisons of the `` Isleworth '' with `` Mona Lisa , '' magnifying their similarities down to the small details . The obvious resemblance , easily visible to the untrained eye , could be evidence that the work is just another copy of the portrait of Lisa del Giocondo that was painted after da Vinci 's masterpiece was completed -- and probably by someone else , Kemp said in a news release . The `` Mona Lisa '' that millions of art lovers flock to gaze upon behind its protective case in the Paris museum was altered from a previous state . `` The Isleworth picture follows the final state of the Louvre painting , '' Kemp said . `` It does not therefore precede the Louvre painting . '' The foundation and Kemp also disagree on the results of modern technical examinations of the `` Isleworth , '' which the foundation has invested in . `` The images produced by infrared reflectography and X-ray are not at all characteristic ( of ) what lies below Leonardo 's autograph paintings , '' Kemp says . Museum displays earliest known Mona Lisa copy . The Mona Lisa Foundation presents historical notations by artists and intellectuals in the 16th century and beyond to back up the possible existence of a second portrait , but Kemp finds it inconclusive . In a 20-minute art history video , its own in-house expert Stanley Feldman , main author of the book , presents the foundation 's detailed arguments . The video also includes sound bites from the director of an Italian museum dedicated to Leonardo da Vinci . `` I believe it is more than possible that there existed two pieces of art , '' said professor Alessandro Vezzosi , director of the Museo Ideale Leonardo da Vinci , pointing to features that could tie the painting to historical references to an earlier work of art . What the brain draws from : Art and how we see it . But Vezzosi does not say directly that he believes the `` Isleworth '' is the predecessor of the world-renowned coyly grinning `` Gioconda . '' In a speech in Geneva on Thursday , Vezzosi again hedged his bets , not backing the foundation 's claim outright but saying it had presented a `` fascinating possibility '' that merited further study . `` The 'Isleworth Mona Lisa ' is an important work of art deserving respect and strong consideration as well as a scientific , historic and artistic debate among specialists rather than a purely media interest , '' he said . He is conducting parallel research in conjunction with another expert , Carlo Pedretti of the Armand Hammer Center for Leonardo Studies of the University of California in Los Angeles , Vezzosi said . Meanwhile , Kemp recommends `` that questions are asked about the relationship of the Foundation to the current owners . '' The Swiss nonprofit was established by bank chairman Markus Frey , financier Daniel Kohler and auctioneer David Feldman , who shares his last name and hometown of Dublin with the foundation 's art historian . It does not divulge who owns the `` Isleworth '' on its website but explains that `` the owners of the painting have endowed The Mona Lisa Foundation with exclusive rights to carry out its objectives . '' If the `` Isleworth '' is not a da Vinci original , as the foundation claims , but a copy , which Kemp thinks is more likely , then it 's not a great one , he says . It does n't quite have that Mona Lisa smile . Scientists unlock secret of Mona Lisa 's face .
A Leonardo da Vinci expert says the claim is worth further research . Swiss Renaissance has what it claims is a link to ` ` Mona Lisa '' An Oxford University scholar cast doubt on its authenticity . The Mona Lisa Foundation exists solely to research this one painting .