The lawyers have plenty of lawyers to guide them on the Shearman & Sterling and Allen & Overy deal to make a $3.4 billion law firm with 3,900 attorneys.

Davis Polk & Wardwell is counseling Shearman on the merger, while Simpson Thacher & Bartlett is advising A&O. Altogether, at least nine outside counsel lawyers between the two firms are on the deal, likely adding a costly legal bill to the merger process.