Sigstr, an e-mail marketing startup based in Indianapolis, says it has raised $5 million in Series A funding.

The investment was led by Hyde Park Venture Partners, which was joined by HubSpot (NYSE: HUBS), Battery Ventures, Grand Ventures, and High Alpha Capital. Investors have pumped a total of $7 million into Sigstr, a company spokeswoman says in an e-mail to Xconomy.

Sigstr’s software turns corporate e-mail signatures into a marketing channel, where staff can reinforce branding strategies and tailor sales pitches. Its clickable “call-to-action banners” are meant to stoke awareness of events, product updates, job openings, and internal communications. Sigstr says its customers include Angie’s List, Terminus, United Way, and the Indiana Pacers basketball team.