Kevin Federline was the target of a possible assassination plot earlier this year.
The Federal Bureau of Investigation (FBI) received information about a risk to the 29-year-old backing dancer's life in June.
FBI spokeswoman Laura Eimiller said. "The FBI received nonspecific, uncorroborated allegations regarding a threat against Kevin Federline."
As the case was not a federal matter, the FBI passed the information to the Los Angeles Police Department (LAPD).
The LAPD then opened an investigation into the threat, but the case was closed after it was determined there was not enough evidence.
LAPD spokeswoman Norma Eisenman said: "We do not have any current investigation pending regarding threats made against Kevin Federline."
Meanwhile, Kevin is currently embroiled in a court battle with ex-wife Britney Spears over the custody of their two children, Sean Preston, two, and one-year-old Jayden James.
The couple - whose divorce was finalised in July - were originally granted joint custody of Sean and Jayden, but Kevin claims Britney's recent erratic behaviour shows she is not a fit mother and wants primary care of the children. | 
