Dive Brief:

• Endurance International Group Holdings Inc says it will buy email marketer Constant Contact Inc for $1.1 billion.
• The deal will allow Endurance to add Constant Contact's online marketing tools to Endurance's portfolio of Web-hosting software for small and medium-sized businesses.
• Constant Contact offers businesses templates to advertise products through emails.

Dive Insight:

Endurance International's Chief Executive Hari Ravichandran said buying Constant Contact will give his company access to half a million new customers. But shares in Endurance slipped following the announcement.

"I think the market will start to understand it a little bit better, but there's definitely a knee-jerk reaction. The unknown always causes anxiety to public investors," Ravichandran said.

Endurance already has an agreement to provide Constant Contact's email marketing tools to its customers.

But Gregg Moskowitz, an analyst with Cowen, questions how many of Endurance's customers will be willing to pay for Constant Contact's solutions.

The deal is expected to close in the first quarter of 2016.