A pair of Boston-area RIAs this week announced they will team up to provide a variety of advisory services to more than 2,000 high net worth clients holding more than $2 billion in assets after discount brokerage E*Trade agreed to sell Wellesley, Mass.-based Kobren Insight Management to Newton, Mass.-based Adviser Investment Management for an undisclosed amount.

The leveraged buy-out by 14 Adviser Investment Management partners and six Kobren partners was signed at the end of 2010 but closed this week. The deal marks the presumptive end of the aggressive expansion into the RIA market E*Trade embarked upon in 2005 with the acquisition of Howard Capital Management, Kobren and Retirement Advisors of America.

Kobren, which was originally a small RIA division of Harrisdirect LLC, was the last of the rolled up RIAs sold, and gives the newly combined a company a golden opportunity to raise its profile and expand its wealth management business.

"We're excited to be partnering with a firm we've always admired," said Adviser Investment Management President Dan Silver. "Combined we'll be one of the top independent registered investment advisors in the country. We're all motivated and excited to get to work and spread the gospel of risk-adjusted, diversified investing."

Silver said the combined firm will retain the Adviser Investments name and will continue to manage customized portfolios of mutual funds, exchange traded funds (ETFs), bonds and variable annuities for individual investors, trusts, institutions and foundations.

For now, all employees at both firms -- a total of 55 advisors -- will retain their positions at the Newton, Mass. headquarters.

The new-look AIM will continue using as many as 30 different broker-dealers for its bond strategies because, according to Silver, it "gives us a larger pool to select from so we're sure we're getting the best price for the client. The firm does not use a broker-dealer on the funds side and typically uses the custodian's no-transaction-fee platform.

Fidelity Investments will serve as AIM's primary custody services provider along with Charles Schwab and E*Trade.

Silver said Fiduciary Network, an affiliate of Emigrant Savings Bank, structured and helped finance the deal.

Adviser Investments Management and Kobren Insight Management were founded in 1994 and 1987, respectively.

Regarding the new management team and structure, Rusty Vanneman, Kobren's chief investment officer, and Chris Keith, its fixed-income strategist, will team up with AIM founder and chairman Dan Wiener and Jim Lowell, the firm's chief investment officer, to lead the newly merged organization.

"This combination allows us to increase the scale of our operations while adding more depth to our team of researchers and portfolio managers," Silver said. "It's a great opportunity for all involved, but most importantly for our clients."