ACCELERATING an industry-wide consolidation trend, law firms in Boston, San Francisco, New York and St. Louis are moving ahead with two separate merger plans to create mega-firms of more than 800 lawyers each.

In a May 24 vote, partners at St. Louis-based Bryan Cave overwhelmingly voted in support of a merger with New York’s Robinson Silverman Pearce Aronsohn & Berman, according to sources at both firms. Robinson Silverman partners are set to vote next week, with a similar outcome expected but not absolutely certain, said a source inside the New York firm. Bryan Cave currently counts 650 lawyers worldwide, while single-office Robinson Silverman has 170 lawyers in New York.