The World Boxing Council (WBC) has absolved the British fighter of intentionally doping after ruling that a "highly-elevated consumption of eggs" was an explanation for his adverse test result.
Benn's fight with Chris Eubank Jr was cancelled last October after it emerged that the fighter had tested positive for the banned fertility drug clomifene.
In a statement, the WBC said that it found "there was no conclusive evidence that Mr. Benn engaged in intentional or knowing ingestion of clomifene".
It said: "There were no failures in the procedures related to sample collection, sample analysis, or violations of Mr. Benn's B Sample rights that would justify questioning or invalidating the Adverse Finding, and Mr. Benn's documented and highly-elevated consumption of eggs during the times relevant to the sample collection, raised a reasonable explanation for the Adverse Finding."
Benn is now back on the WBC rankings after the ruling but remains under investigation by UK Anti-Doping and the British Boxing Board of Control - meaning that he is still unable to fight in the UK.
The fighter had previously blamed "contamination" for the failed tests.
Benn's promoter Eddie Hearn has said that the boxer is "ready to resume his career".
He told the Boxing Social podcast: "This is now about finding places for Conor Benn to box.
"Conor Benn can box anywhere in the world, but to box in the UK he has to go through a process, and we don't know how long that process is going to take.
"He's in the gym. He's been in the gym for the last six weeks. He's ready to fight."