Account aggregation could be the killer application of asset gathering. Firms are hoping their brokers will be able to get a look at all their clients' assets and liabilities through a broker opt-in feature that will be available from Yodlee around midyear.

No third party can access customers' consolidated statements, including their brokers or the firms, unless clients grant permission. Optimism is running high that they will.

We did some focus groups, and 80% of our clients told us they would opt in to share with their FCs, says Everett Berger, director of digital business development at Merrill Lynch.

The firm is already encouraging clients to share hard-copy aggregated statements with their brokers. Merrill is also developing a share-with-your-FC button that will allow clients to send a single snapshot view of their accounts to their brokers, Berger says. No release date for the button has been set.

Merrill's idea differs from the opt-in mechanism that Yodlee is developing, according to Sandy Motusesky, Morgan Stanley Dean Witter's senior vice president for interactive marketing. Yodlee's plan allows the client to give a broker access to, say, the net worth part of the statement while shutting off access to e-mail and bank accounts, she says.

To develop new business, Salomon Smith Barney allows nonclients to register as guests and use the aggregation service, says Steve Clifford, director of interactive marketing and services.

Motusesky says that sometime around midyear, MSDW will make its service available to nonclients. It might ask these users to register as a means of generating leads.

Merrill is working on the same idea, Berger says. No date has been set for a rollout.

Even at its most basic level, the aggregation service can be a valuable, timesaving tool for brokers and clients alike, Berger says. A lot of clients are bringing in piles of statements now, he says.

In March, Merrill and MSDW began online broadcasts to brokers on how to use account aggregation with clients.

The account aggregator at .