A United States federal appeals court has reversed the ruling declaring the ongoing bulk phone metadata collection program of the National Security Agency (NSA) illegal.

The Court of Appeals for the District of Columbia has rejected conservative lawyer Larry Klayman's claim that the Obama administration has violated his constitutional rights through the NSA's bulk surveillance program. In its ruling, the three-judge court says Klayman failed to provide evidence that he had suffered from "concrete and particularized" injury as the subject of NSA surveillance.

"Plaintiffs claim to suffer injury from government collection of records from their telecommunications provider relating to their calls," says (pdf) Senior Circuit Judge Stephen Williams in his opinion. "But plaintiffs are subscribers of Verizon Wireless, not of Verizon Business Network Services, Inc.-the sole provider that the government has acknowledged targeting for bulk collection."

Judges Janice Rogers Brown and David Sentelle agree, saying that the evidence leaves doubts about whether Klayman's information were actually collected by the NSA. The case has been sent back to a district court, where Judge Richard Leon, who ruled that the program was almost certainly unconstitutional, will decide whether Klayman was able to provide proof that his phone records were obtained by the NSA.

For his part, Klayman calls the decision "an outrage," saying that the judges have committed "intellectual dishonesty" in denying the nature of the NSA's bulk surveillance program, which was leaked in documents by whistleblowers Edward Snowden and Julian Assange.

The program was created following the Sept. 11, 2001 attacks by the Bush administration as a way to identify local connections with terrorists abroad by collecting American phone records, including all information about the time of call, duration of call and location of callers but not the content of calls.

However, the U.S. Patriot Act, which was used as the legal basis for the program has expired in June, following the decision of another U.S. appeals court declaring that the law never authorized the program. In the wake of the law's expiration, Congress immediately passed the Freedom Act, which limits the NSA's collection power by requiring the agency to obtain a court warrant before being able to gain access to the specific phone records stored by telephone companies.

To date, the bulk collection program continues until six months after the expiration of the Patriot Act, which the Foreign Intelligence Surveillance Court says will give the NSA enough time to set up a new system that complies with the Freedom Act.