The agreement essentially rolls what could have been a six-game suspension into four games. Jackson currently is serving a three-game NFL suspension for violating the league's substance-abuse policy. He pleaded guilty in February to his second DUI since 2006.
On Aug. 20, the Chargers placed Jackson on the roster-exempt list, meaning he'd be suspended for three games once he signed with the team. But Jackson's representatives believed he shouldn't have to serve that suspension if he was traded to another team.
The agreement, which settles a grievance filed by the NFL Players Assocation, stipulates that if Jackson signs a contract with the Chargers and is traded by 4 p.m. ET Wednesday, he will be placed on the commissioner exempt list for three games, retroactive to Game 2. That means Jackson would be able to play in his new team's fifth game.
If Jackson isn't traded by the deadline, he'll have to serve the remainder of his three-game DUI suspension and the entire three-game suspension on the roster-exempt list if he does sign, regardless of a subsequent trade.
The Minnesota Vikings reportedly are interested in Jackson, who's coming off two consecutive 1,000-yard seasons.
A moratorium will be in effect until 4 p.m. ET Friday, during which any team interested in trading for Jackson must receive permission from the Chargers before speaking with his agents about contract terms. Trade compensation must be directly negotiated with the Chargers. San Diego might not trade Jackson until after the moratorium has expired.
If Jackson is traded before Wednesday, he'll be allowed to report to the new club and, at the team's discretion, be eligible to participate in activities permitted by the substance-abuse policy for the remainder of his suspension. When the DUI suspension ends, he'll be permitted to practice with his new team under the roster-exempt rules before the fourth game, but he won't be available to play and cannot be paid until the fifth game.
Jackson's agents said earlier this month that they had worked out a deal with another team, which they didn't identify, but it fell apart because the Chargers wanted too much in return for the receiver.
Unhappy over not receiving a long-term deal, Jackson refused to sign the one-year, $3.268 million contract he was tendered as a restricted free agent. When he and holdout left tackle Marcus McNeill didn't sign their tenders by June 15, the Chargers were entitled to offer them 110 percent of their 2009 salaries, essentially cutting $2.5 million off the tenders. If either player reports this year, it would be for the final six games in order to accrue a season toward unrestricted free agency.
Chargers general manager A.J. Smith placed Jackson and McNeill on the roster-exempt list on Aug. 20, a hardball tactic to try to end the impasse.
McNeill's agent, Alvin Keels, told NFL Network insider Jason La Canfora that he hasn't been contacted by the NFL or the NFLPA to notify him if the Jackson ruling applies to his client, but "I would have to assume it does under the circumstances."
However, Keels said he doesn't believe the Chargers have any inclination to deal the Pro Bowl left tackle. While Jackson was granted permission to seek a deal with at least two teams, McNeill hasn't been granted that right.
"I don't think they want to trade Marcus," Keels said.
According to a league source, Keels asked the Chargers for permission to speak with three teams regarding a deal and was denied on all counts. So, without a trade, the Jackson ruling today is a moot point as applied to any other party.
Smith didn't return a call seeking comment.
The Associated Press contributed to this report.