Lashback, the company whose services help marketers tell whether affiliates are honoring opt-out requests and complying with the Can-Spam Act, is launching a new service called ListMonitor.

The new service allows e-mail marketers to monitor the mailing behavior of firms with which they share data, according to LashBack vice president of marketing James O’Brien.

He said currently, e-mail marketers employ people to manually seed e-mail lists with dummy names to see what their partners are doing.

“We’ve put together a Web-based software package that automates that process,” he said.

He added the service can be used with existing seeding accounts, Gmail, AOL, Yahoo MSN Hotmail accounts, and custom domains provided by LashBack.

Among the things marketers using ListMonitor can check for are the volume of mail partners send, whether or not they are honoring their mailing contracts, and whether or not they are Can Spam compliant.

The service also allows marketers to see how firms from which they buy data, such as a co-registration partner, behave, said O’Brien.

“If you’re going to buy data from a data source and you know where they’re collecting it, you’re going to be able to see what kind of saturation those lists in that dataset are getting in terms of how many other people are mailing to it,” said O’Brien.

ListMonitor starts at $1,000 a month.

Lashback’s other business-to-business services are UnsubMonitor and Can Spam Compliance Monitor, which help marketers tell if affiliates are honoring opt-out requests and are complying with Can-Spam Act requirements.