One factor boosting Kirkland’s profitability is its huge nonequity partner class. A little more than half of Kirkland’s 709 partners are "nonshare" partners, as the firm calls them. Kirkland asso­ciates make partner earlier than at most firms, after six years, and they generally work another three to four years before they find out if they’ll be selected for share status or must leave. Most recently the firm made 84 nonshare partners, and promoted 22 to share status.

"That is the key to understanding Kirkland & Ellis," asserts former Kirkland equity partner Paul Cappuccio, now executive vice president and general counsel of Time Warner Inc. "The firm makes a ton of money on [the nonshare partners], and they work a ton of hours. It is the engine. It is genius. And it’s good for young lawyers. But you have to do it right. You have to train them well and have some selectivity."