The sides announced Saturday night that they had finally reached an agreement, eight days after a 30-day exclusive negotiating window expired. The group is headed by Pittsburgh sports attorney Chuck Greenberg.
"Together, we have worked exhaustively since last month to attain this agreement," Hicks said in a statement. "It's a complex business deal that positions the franchise positively for the future."
The purchase price is expected to be more than $500 million.
The next step is the deal has to be reviewed by baseball's executive and ownership committees. Then at least 75 percent of baseball owners would have to approve the transfer of ownership from Hicks to Greenberg's group.
A group of 40 lenders holding debt from Hicks Sports Group also has to approve.
There is a chance the deal could be approved before the April 5 opener, though the process could continue into the season.
Hicks Sports Group defaulted early last year on $525 million in loans tied to the Rangers and the NHL's Dallas Stars, which Hicks has owned since 1996. Hicks has said that was a deliberate move to force lenders to renegotiate terms of the deals.
Hicks, who bought the Rangers in 1998, put the team up for sale to help pay off or reduce that debt. He has said he plans to keep his NHL team.
Greenberg has asked Hicks to continue his association with the Rangers as chairman emeritus.
"Nolan and I greatly appreciate Tom Hicks' willingness to work beyond the deadline to complete the deal and his support for passing the torch from the Hicks family to our group," Greenberg said. "His actions speak eloquently to his commitment to serve the best interests of Rangers fans and the community."
In a separate transaction, Ballpark Real Estate, L.P., an independent investment vehicle controlled by Hicks, will sell or transfer to the Greenberg-Ryan group approximately 153 of 195 acres around Rangers Ballpark and Cowboys Stadium that is owned or controlled by Hicks. In return, Hicks will receive cash, notes, and an ownership position in the team.
Hicks announced Dec. 15 that he was entering in exclusive negotiations with Greenberg, choosing that proposal over bids submitted by former sports agent Dennis Gilbert and Houston businessman Jim Crane, who at the end of the 2008 season attempted to buy the Houston Astros from Drayton McLane.
At one point before going into negotiations with Greenberg, Hicks was trying to put together a group of local investors for a bid in an effort to maintain controlling ownership of the team.
After the 30-day exclusive negotiating window expired on Jan. 15, Greenberg and Ryan issued a midnight statement saying they had "come too far to walk away now" and were prepared to work around the clock if that's what it took to reach a final agreement.
If the deal is approved by baseball, Greenberg will become managing general partner and CEO of the Rangers while Ryan will continue as team president, the position he was hired for two years ago.