Hub was traded on the New York Stock Exchange and Toronto Stock Exchange until 2007 when it was acquired by the private equity firms Apax Partners and Morgan Stanley Principal Investments. The firm operates 250 offices across North America.

USI has 80 offices in 23 states and is owned by Goldman Sachs Capital Partners, a private equity division of Goldman, Sachs & Co. It also went private in 2007.

Both firms are considered to be among the top 15 brokers in the world.

The firm suggests Cooper Gay Swett & Crawford and Hyperion Insurance Group may also consider going public. Both are based in London and Stifel Nicolaus suggests they are potential candidates for foreign initial public offerings.

Cooper Gay was formed in 2010 with the merger of Cooper Gay in London and San Francisco-based wholesaler Swett & Crawford. The firm employs 1,400 people operating in North America, South America, Europe and Asia.

Hyperion Insurance Group has 50 offices in 25 countries employing 850 people. It is an insurance-brokerage firm that also operates an underwriting unit.

The insurance-brokerage marketplace as a whole, Stifel Nicolaus says, will benefit from an insurance market that is continuing to show signs of rate increases. Rate increases will mean an increase in commission revenue and margin expansion as “expense will remain largely unchanged.”

A projected 10 percent rise in insurance rates “could boost operating margins by 160 basis points,” the report says.

During the last hard market that ran from 2000 to 2004, the five public brokers (Aon, Arthur J. Gallagher, Brown & Brown, Marsh and Willis) reported average operating earnings per share, compound annual growth rate of almost 19 percent, says Stifel Nicolaus.

The analyst notes that rates are pressured from the steady decline in prior-period reserve development and the rise in commercial lines combined ratios that are expected to hit 110 for 2011. Insurers are also unable to offset their underwriting losses with investment income as investments suffer from low interest rates.

While the brokers are expected to benefit from rising rates, among the publicly held brokers, Willis could experience margin pressure as it works to “reverse recessionary expense controls.” Brown & Brown will deal with pressure on organic growth from the “economically weakest domestic regions” where it does business, primarily Florida.