The two firms announced an all-stock transaction, valued at more than $300 million, to merge operations on or close to 30 June, subject to approval by Weisel shareholders and regulators.

“With the merger, Stifel's revenue mix remains balanced between its institutional group and global wealth management segments,” Ronald  Kruszewski, chairman and chief executive of Stifel Financial, said in a statement.

Last month Stifle acquired Missouri Valley Partners, an investment advisory firm, from First Banks.