Thomas Weisel Partners Group, Inc., also known as TWP or Weisel, is a U.S. growth focused investment banking firm based in San Francisco, California.
The firm was launched in January 1999 by Thom Weisel and other personnel from the former Montgomery Securities. In 1997, Thom Weisel helped to orchestrate a $1.3 billion acquisition of Montgomery Securities by NationsBank. The following year, however, NationsBank acquired BankAmerica Corp, which itself had acquired Technology-based rival Robertson Stephens. A culture clash and fight for control ensued at the newly combined investment banking units of what is now known as Banc of America Securities. In the process, senior bankers from Montgomery Securities secured backing from the Silicon Valley Venture Capital community and left to form their own venture: Thomas Weisel Partners. Source