The lawsuit, filed by Democratic and Republican attorneys general, portrays a close-knit circle of generic drug executives and sales representatives who regularly socialize at conferences and gatherings like golf outings, cocktail parties and "girls' night out" events in the New Jersey area, where many of the companies are based.
But the collegial relationships, while common in many industries, veered into more overt anticompetitive tactics, Mr. Jepsen, Connecticut's attorney general, said.
"It's very damning," he said. "It reveals a culture of cronyism where, whether it's over a game of golf or a dinner or drinks, there's just systematic cooperation."
He described the behavior as deliberate. "There's nothing hidden about it," he said.
In the case of doxycycline, the complaint says that in 2013 Heritage contacted Mylan, the only other maker of a delayed-release version of the product at the time, and told executives there that Heritage planned to release its own version. According to the complaint, Mylan agreed to "walk away" from at least one major wholesaler and one large pharmacy chain to allow Heritage to gain a foothold in the market. The complaint quotes from emails that are redacted in the publicly available version and that the suit says show how Mylan and Heritage executives hammered out the details.
When a third competitor, Mayne, planned to enter the doxycycline market in 2014, it contacted Heritage and Mylan to negotiate details of how prices would be set and customers would be allocated, the suit says.