Fiduciary Network has entered an agreement to invest in Adviser Investments and finance its acquisition of Kobren Insight Management from E*Trade Financial.

The transaction brings together two firms that were conceived out of newsletter businesses. Dan Wiener originally ran a newsletter for Vanguard investors before starting Adviser Investments, which today manages $1.2 billion. Eric Kobren ran a newsletter for Fidelity investors before launching Kobren Insight Management , which manages about $1 billion. E*Trade bought Kobren's firm in November 2005.

At least six principals in Kobren are becoming principals in Adviser Investments, which will have 20 partners. Kobren's offices are located five miles from Adviser Investments' headquarters in Newton, Mass.

Mark Hurley, CEO of Fiduciary Network, says the transaction will nearly double the merged firm's revenues, but it will more than double the bottom line. Many costs, like two separate offices, can be eliminated and Adviser Investments will now have two prospecting lists and a deeper bench on both the business and investments sides.

Hurley was approached last year about buying Kobren and says he approached Adviser Investments because it was a perfect fit, given the strikingly similar evolution of both firms. "This presages a lot of what you are going to see in this business," he predicts.

Fiduciary Network was launched in 2007 by Hurley, the former CEO of Undiscovered Managers, and New York real estate tycoon and financier Howard Milstein to purchase stakes and finance ownership transitions in RIA firms. The Adviser Investments transaction will be its 12th deal.