A portrait signed and dated 1608, believed to be the only one of playwright William Shakespeare during his lifetime, is now on sale for more than £10 million ($11 million) in London.

The anonymous owner is selling the piece done by Robert Peake, court painter to King James I, through a private contract without an auction. It was displayed at the Grosvenor House hotel in London on Wednesday. Prior to 1975, the picture hung in the library of a home in England belonging to the Danby family and has been in private ownership ever since.

According to those organizing the sale, “extensive” connections existed between Shakespeare and Peake who was believed to be commissioned to paint portraits of high-ranking members of the court and Jacobean society.

The Office of the Revels, which oversaw the presentation of plays, is believed to also have commissioned the artist and worked in Clerkenwell, London, where some of Shakespeare’s plays were rehearsed.

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Only two paintings of the playwright, both done after his death, are seen as validly representing him – one being an engraving on the title page of the First Folio, published in 1623 which is a printed collection of his plays assembled by his colleagues seven years after his death. The second is the sculpture at his funeral monument in Stratford-upon-Avon. Shakespeare died in 1616, aged 52. 

Art expert Duncan Phillips, who investigated the work ahead of the sale, said, “There is more evidence for this portrait of Shakespeare than any other known painting of the playwright."

"It is a monogrammed and dated work by a portrait painter of serious status with connections to the artist who produced the image for the First Folio," he said, adding, “The picture has survived the past 400 years almost untouched by wear and tear thanks to its ownership by a family of Shakespeare enthusiasts who hung it in their library.”

According to Shakespeare expert Michael Dobson, relaying to the Daily Mail, the suggestions claiming that the painting is of Shakespeare are “wishful thinking”, considering that numerous claims and counterclaims over the legitimacy and credibility of paintings have risen in previous years.

Botanist and historian Mark Griffiths announced back in 2015 his discovery of what he believed is the only authentic portrait of Shakespeare, commenting that the engraving on the title page pertaining to a 400-year-old book, either The Herball or Generall Historie of Plantes, has four identifiable figures, one of whom was Shakespeare, also known as the Bard, aged 33.

The National Portrait Gallery experts in London declared in 2005 that The Flower Portrait dating back to the early 19th century, was fake. Historians disagreed about the origins bearing the inscription 1609.

Afterward in 2009, a portrait of the playwright on display in Stratford-upon-Avon became a controversial after the former director of the Victoria and Albert Museum and the National Portrait Gallery, Sir Roy Strong, claimed that the beliefs that the painting was of Shakespeare were “codswallop”.

However, organizers of the Shakespeare Found exhibition stated at the time the painting was of Shakespeare.