The Big 12 announced West Virginia's acceptance on Friday, but the Big East said it would hold the Mountaineers to a provision in the conference bylaws that requires notice of 27 months before a school can withdraw.
The lawsuit asks the Monongalia County Circuit Court to declare the bylaws invalid, claiming that the Big East breached its fiduciary duty to West Virginia by failing to maintain a balance between football-playing and non-football members.
The complaint, which asks for a jury trial, also alleges that the Big East agreed to West Virginia's immediate withdrawal by accepting a $2.5 million down payment on its $5 million exit fee.
"Absent a Court order permanently enjoining the Big East from enforcing the 27-month notice provision against WVU, WVU has no adequate remedy at law to protect its interests and will suffer continuing and irreparable damages and injury," the lawsuit says.
Big East spokesman Chuck Sullivan said the league's position is that West Virginia is not eligible to join the Big 12 until July 1, 2014, but he declined to comment on the lawsuit.
WVU spokesman John Bolt also declined to elaborate, saying "the lawsuit speaks for itself."
The lawsuit is the latest development in a flurry of conference realignment activity this fall. Syracuse and Pittsburgh withdrew from the Big East in September to join the Atlantic Coast Conference.
TCU accepted an invitation to join the Big East in September but switched to the Big 12 in October and was not required to honor the 27-month notice requirement.
"That's basically because they never started with the Big East," Sullivan said of the Horned Frogs. "Because they had not formally joined the conference, which would have been July 1, 2012, they were subject only to the financial component."
West Virginia's lawsuit says other Big East football members — Connecticut, Louisville, Rutgers and Cincinnati — "have been engaged in discussions with other sports conferences," so when the Big 12 extended its invitation Friday the Mountaineers accepted.
"As the Big East, in less than two months, had denigrated into a non-major football conference whose continued existence is in serious jeopardy, WVU had no choice but to accept the Big XII's offer," the lawsuit says.
The complaint says the departures of Pitt and Syracuse left the Big East with only six football members and eight non-football members — an imbalance not contemplated by the bylaws, which therefore should be declared null and void.
The complaint also alleges that the Big East and its commissioner ignored recommendations by football members to maintain the league's level of competitiveness in that sport and advanced the interests of the non-football members.
"This lack of leadership, breach of fiduciary duties by the Big East and its Commissioner, and voting disparity between the football and non-football schools resulted in the Big East football conference no longer being a viable and competitive football conference," the complaint says.