Cravath, Swaine & Moore’s decision to move away from the pure lockstep model that has defined the firm for decades marks a pivotal moment in Big Law and an indirect admittance of one of the biggest trends in the past few years: pure lockstep firms are losing favor in the war for top talent.

For decades, America’s white-shoe law firms seemed to have impenetrable armor, unscathed by what happened in the broader legal industry. But the last few years have revealed weaknesses that would once have been considered unthinkable, as rising powers like Kirkland & Ellis and Paul, Weiss, Rifkind, Wharton & Garrison have begun luring talent away from storied firms like Wachtell, Lipton, Rosen & Katz and Simpson Thacher & Bartlett.