Robson, who has worked with stars including Britney Spears and Justin Timberlake has asked a California judge to allow him to make a late creditor's claim against Jackson's estate for "childhood sexual abuse".
Jackson's estate attorney Howard Weitzman has now blasted Robson's allegation, pointing out that he took to the stand at the singer's 2005 child molestation trial to deny he had ever been molested by the Thriller hitmaker during several sleepovers.
In a statement to Tmz.com, Weitzman says, "Mr. Robson's claim is outrageous and pathetic. This is a young man who has testified at least twice under oath over the past 20 years and said in numerous interviews that Michael Jackson never did anything inappropriate to him or with him.
"Now, nearly 4 years after Michael has passed, this sad and less than credible claim has been made. We are confident that the court will see this for what it is."
Jackson died from an accidental overdose of prescription drugs in 2009.