The Savages actor and his attorney Marty Singer had been the subject of a lawsuit filed by author Robert Randolph.
Randolph had claimed that the duo had attempted to discredit him by sending a letter to Gawker denying allegations made by Randolph in a piece called The Secret Sex Life of John Travolta.
In Singer's letter, he wrote that Randolph had "suffered from brain damage" and "spent time in mental institutions", which Randolph alleged damaged his reputation.
In the suit, Randolph claimed that Travolta and Singer "sought to disparage the quality of [his] property and reputation and to induce members of the public to believe [he] is an unreliable source and thus abstain from purchasing" his book.
However, Judge Malcolm Macky has now dismissed the case, E! Online reports.
He explained that Singer's letter is not subject to a defamation claim because it was a "protected pre-litigation demand letter", saying: "Defendant Singer has amply established that he sent the 11/23/10 letter to Gawker Media in good faith and in serious consideration of litigation. As such, the letter is privileged."
Judge Macky also claimed that Randolph "submitted no evidence" to support his claim that people were deterred from buying his book.
Earlier this year, Travolta and Singer denied rumours that they had paid off men who dropped their lawsuits accusing Travolta of sexual misconduct.