The NBA filed a federal lawsuit against the league's players union on Tuesday, hoping to establish the legality of the lockout imposed a month ago and protect against a possible players lawsuit.
League officials also announced Tuesday they were filing an unfair labor practice charge against the National Basketball Players Association, claiming the union has not bargained in good faith.
The moves come one day after talks that produced mo movement and just over a month after the previous collective bargaining agreement between club owners and players expired, sparking the second shutdown in NBA history.
Owners claim losses and seek salary cuts and a firm payroll cap while players hope to keep things basically as they have been under the old deal made in 2005. Each side has pocketed about half of $4.3 billion in annual revenues.
The NBA move takes a page from the NFL lockout that concluded last week, when American football's union decertified so players could press an anti-trust case in US courts, in part to attack the legality of the lockout.
NBA players union leaders have mentioned decertification and an anti-trust lawsuit as a possible tactic in negotiations with the NBA, something the league seeks to prevent with the labor charge and lawsuit against the union.
"These claims were filed in an effort to eliminate the use of impermissible pressure tactics by the union which are impeding the parties' ability to negotiate a new collective bargaining agreement," NBA deputy commissioner Adam Silver said.
"For the parties to reach agreement on a new CBA, the union must commit to the collective bargaining process fully and in good faith."
The league's lawsuit wants to establish the lockout as not being a violation of US anti-trust laws and that if a union decertification was declared lawful, that all current player contracts would be void and unenforcable.
In the NFL lockout, players have voted to reinstate the NFL Players Association as a union, but only as a condition of final approval of a settlement deal reached at the negotiation table.
The NBA shows no signs of being near that point as players ponder signing with teams in other nations for the duration of the lockout and fans wonder if the season will begin on November 1 as scheduled.
"We haven't seen any movement. There's still a very wide gap between us," NBA commissioner David Stern said. "I don't feel optimistic about the players' willingness to engage in a serious way."
Not since the 1998-99 NBA season was trimmed to 50 games has their been an NBA shutdown until now. Some of the NBA club owners involved also owned National Hockey League clubs when that league lost the entire 2004-05 season to a labor dispute.
"We're continuing to try to work around what's been said and really focus on the deal on the table," union president Derek Fisher said. "Right now we're still a very, very long way from getting a deal done."