Zaid al-Hilli, 54, was arrested in June on suspicion of conspiracy to commit murder.
"The 54-year-old man, from Chessington, was arrested on [June 24] on suspicion of conspiracy to commit murder and interviewed as part of the ongoing investigation. At this stage there is insufficient evidence to charge him with any criminal offense and no further police action is being taken at this time," the Mirror reported a Surrey police spokesman said.
Al-Hilli's brother, Saad al-Hilli of Claygate, was found shot to death along with his wife Ikbal, her mother Suhaila al-Allaf, who lived in Sweden, and Sylvain Mollier, a passing French cyclist, on a remote forest road in Chevaline, France, Sept. 5, 2012.
The slain couple's eldest daughter, Zainab, then 7, survived the attack with severe head injuries, and their youngest daughter, Zeena, then 4, hid under her dead mother's skirt inside the vehicle and was uninjured.
Zaid al-Hilli admitted he and his brother argued over an inheritance after their mother's dead but he said it was "ridiculous" to accuse him of arranging for his brother to be killed, the Guardian reported Wednesday.