Prosecutors dropped the charges against Adnan Syed – the topic of the hit Serial podcast – three weeks after his murder conviction was lifted.
A further round of DNA testing follows, a lawyer familiar with the proceedings said.
Mr. Syed, now 41, was sentenced to life in prison in 2000 for the alleged murder of his girlfriend Hae Min Lee. He was 18 at the time.
A judge in Baltimore overturned his sentence on 19 September after prosecutors said two other possible suspects had not been revealed to the defense during the trial.
After being released, Mr. Syed was placed in home detention with GPS tracking.
District Judge Melissa Phinn gave prosecutors 30 days to try again or drop the charges.
On Tuesday, the Baltimore City State Attorney’s Office confirmed that it had filed the lawsuit against him.
Attorney Laura Nirider, who accompanied Syed when he was released from prison last month, said he was “formally released”.
Ms. Nirider, co-director of the Center on Wrongful Convictions at Northwestern Pritzker School of Law, tweeted: “Breaking News: After the latest round of DNA testing generated results that, like previous rounds of testing , excluded Adnan Syed, has now been formally exonerated! “
Mr. Syed has been in prison for more than 20 years. Image: AP
Last week, court documents were filed in support of an appeal by Ms. Lee’s family.
While they are not contesting Mr. Syed’s release, they want the judge to hold another hearing to allow them to go to court, attorney Steve Kelly said.
Mr. Syed, who has maintained his innocence for decades, came to public attention in 2014 during Serial’s debut season.
Doubts have been raised about some of the evidence used in his case, including cell phone antenna data.
The additional suspects were known at the time of the original investigation and were not adequately excluded or disclosed to the defense, prosecutors said.
New information showed that one of the suspects was convicted of serial rape and sexual assault, they added.
