Agents for players have been asking the union for several months to file a grievance.
"It preserves the players' claims, and the commissioner's office hasn't admitted any wrongdoing," union general counsel Michael Weiner said Tuesday. "I would characterize this as a standstill agreement."
The deal, agreed to last week, allows both sides to view how this offseason's free-agent market develops. There are few stars in this winter's class, and agents expressed concern last summer that no major players eligible for free agency agreed to contract extensions.
Commissioner Bud Selig has denied any conspiracy against free agents. Rob Manfred, Major League Baseball's executive vice president for labor relations, confirmed the agreement but otherwise declined comment.
Players filed collusion grievances following the 1985, 1986 and 1987 seasons and, after arbitrators ruled for the union, management settled the cases for $280 million.
In addition, the sides in 2006 settled potential claims that management may have conspired against free agents following the 2002 and 2003 seasons. That deal, made with no admission of guilt, called for a lump-sum $12 million payment from money already earmarked for players to settle unfiled collusion claims along with other pending grievances.
Separately, players and owners have had an agreement since last year extending the deadline to file a collusion grievance over the lack of offers to Barry Bonds after the 2007 season. That deal says the union has until after the end of Bonds' criminal trial to file a grievance.
Bonds' trial, on charges he obstructed justice and made false statements to a grand jury, has been delayed while federal prosecutors appeal evidentiary decisions of the district judge.
Weiner has been designated to succeed Donald Fehr as union head, and a final vote is scheduled for December.