Los Angeles, California (CNN) -- Dozens of Michael Jackson songs never heard before by fans will be released in 10 new albums over the next seven years, starting in November, according to a source close to the transaction.
The albums are part of a deal with Jackson's estate that could bring in $250 million to the late pop star's trust, the source said Tuesday.
When Jackson died last summer, he left behind huge debts -- estimated at about $500 million -- but he also owned a valuable music catalogue and dozens of unreleased recordings.
Sony's Columbia Epic Records, Jackson's record label for three decades, will "create new projects for Michael Jackson featuring the never-before-released Jackson recordings," Sony said. "The first project featuring unreleased music is expected for release in November 2010."
The Sony contract was negotiated by John Branca and John McClain, the two men Jackson named in his will to run his estate.
"By all objective criteria, this agreement with Sony Music demonstrates the lasting power of Michael's music by exceeding all previous industry benchmarks," Branca said in a written statement released Tuesday.
Los Angeles County Judge Mitchell Beckloff, who is overseeing the probate of Jackson's estate, has approved the contract, according to the estate source, who asked not to be identified because he was not authorized to speak about details.
Fans can also look forward to re-releases of Jackson's solo albums. Epic already struck gold when it released the 25th-anniversary edition of "Thriller," which rose to the top of the sales charts in 2008.
"Nowhere did Michael set the bar higher than he did with 'Thriller,' which nearly three decades after its release by Epic remains by far the best-selling album in history worldwide with music that transcends generations," said McClain, a former music industry executive who now helps run the estate.
Sony released the album companion to the documentary "This Is It" last fall.
"Michael has always been a treasured member of the Sony Music family," said Columbia Epic chairman Rob Stringer. "We're dedicated to protecting this icon's legacy, and we're thrilled that we can continue to bring his music to the world for the foreseeable future."
Profits from Jackson's estate go into a trust that is shared by his mother and three children. Unchosen charities also will get 20 percent of the estate profits under Jackson's will.
Branca and McClain have not yet been given full powers as executors over the estate, since the judge is still overseeing the probate process.
Joe Jackson, the singer's father, is still trying to challenge Branca and McClain's appointment, but so far his legal efforts have been rejected by Beckloff.