"There's nothing to prevent a player on the exempt list without a contract from signing a new one," league spokesman Greg Aiello wrote Thursday in an email to The Associated Press.
NFL free agency begins Tuesday.
However, 26-year-old Hardy's playing status remains in limbo. He isn't allowed to play until he's removed from the exempt list, which could prevent teams from going after him in free agency.
The league opened its own investigation after domestic violence charges against him were dropped on Feb. 9. It has uncovered enough evidence so far to warrant suspension, a league source told ESPN.com's David Newton.
Hardy met with NFL officials Wednesday in New York to discuss his domestic violence case, but no resolution has been announced.
One point of Wednesday's meeting was to get Hardy to turn over evidence from his July 15 bench trial in which a Mecklenburg County judge found him guilty of assaulting and threatening to kill his ex-girlfriend Nicole Holder. That verdict was set aside when Hardy requested the jury trial that never occurred because the charges were dropped on Feb. 9 as Holder refused to cooperate with the Mecklenburg County (North Carolina) District Attorney's office after reaching a financial settlement with Hardy.
According to a report on NFL.com, Hardy turned over documents from his case.
The NFL has been seeking photos, the trial transcript and other physical evidence from the May 13 crime scene to help with its investigation.
That investigation suffered a setback when the league's court motion to unseal evidence from the bench trial had to be withdrawn because the evidence already had been returned to the district attorney's office and Hardy's attorney, Chris Fialko.
The district attorney's office does not return evidence from a case, leaving it to Hardy and his attorney to decide whether to turn over evidence that could incriminate Hardy.
Hardy was accompanied Wednesday by an attorney representing the NFL Players Association, according to a league source. The NFLPA is arguing that Hardy, if found to have violated the personal conduct policy, should be punished under the old policy under which a two-game suspension was given to first-time offenders.
That body is arguing that since Hardy initially was charged in May, he shouldn't be held to the new policy, which was adopted in late August. That policy calls for a minimum six-game suspension for a first-time offense of domestic violence.
Hardy received $13.1 million from the Panthers last season despite playing in only one game. The team is not expected to re-sign him.
Hardy remains in the prime of his career and had 15 sacks in 2013, tying a Panthers franchise record.
ESPN.com Panthers reporter David Newton and The Associated Press contributed to this report.