Here is a timeline of key events from the NHL's fourth labour dispute in 20 years.
Jan. 6 - League and players reach a tentative 10-year deal on a new collective bargaining agreement after 16-plus hour negotiating session that began on Saturday.
Dec. 20 - NHL cancels all games through Jan. 14.
Dec. 14 - NHL files class-action complaint against the players' union in New York federal court, as well as an unfair labour practice charge with the National Labor Relations Board.
Dec. 10 - NHL cancels all games through Dec. 30.
Dec. 6 - Labour talks collapse, NHL Commissioner Gary Bettman says "disappointed beyond belief" at state of negotiations.
Nov. 26 - League and players agree to allow U.S. federal mediators into the negotiating process.
Nov. 23 - NHL cancels two more weeks of regular season games, wiping out all action through Dec. 14, as well as scrapping the Jan. 27 All-Star Game in Columbus.
Nov. 2 - Annual outdoor Winter Classic scheduled for New Year's Day at Michigan Stadium, which seats more than 100,000 people, is called off.
Oct. 26 - NHL cancels regular-season games through Nov. 30.
Oct. 19 - NHL cancels third week of regular season, wiping out 53 more games and bringing the total number of canceled games to 135 through Nov. 1.
Oct. 18 - Players' union presents three counter-proposals that NHL turns down immediately and calls "a step backward."
Oct. 16 - League offers players six-year deal that includes an equal split of revenue, no rollbacks on existing contracts and allows for a full 82-game season to begin on Nov. 2.
Oct. 4 - NHL cancels first two weeks of the 2012-13 regular season, impacting 82 games that were scheduled from Oct. 11-24.
Sept. 16 - NHL locks out players, essentially halting all league operations, after previous collective bargaining agreement expires with both sides at odds over how to split $3.3 billion in revenue.
Sept. 13 - NHL Board of Governors gives league commissioner Gary Bettman unanimous support to impose lockout if new deal is not reached by 12:01 a.m. ET (0501 GMT) on Sept. 16. (Compiled by Frank Pingue in Toronto; Editing by John Mehaffey)