Class-action law firm Milberg LLP is close to a settlement that could end a federal prosecution of the firm for alleged kickbacks, according to two people familiar with the discussions. The deal would mark the climax of a case that has roiled the American plaintiff's bar.

While a deal could still fall apart, the sides have made progress after weeks of talks that have centered on the payment Milberg will have to make as part of a settlement. Last summer, prosecutors had sought about $50 million in fines and penalties, but the demand mushroomed this year to about $100 million, say people familiar with the negotiations. Recently, Milberg and prosecutors have zeroed in on a payout in the neighborhood of $75 million, these people say.

The government alleged that the firm paid more than $11 million in kickbacks to clients in exchange for their serving as lead plaintiffs in securities class actions. These payouts allowed the firm to quickly file suits and become lead counsel, prosecutors allege, entitling Milberg to a large share of the fees: some $250 million over more than two decades. The firm, which is scheduled to stand trial in August, has denied wrongdoing.