The Riverside Co. has acquired Mercareon as an add-on acquisition for portfolio company Transporeon.

Mercareon, headquartered in Ulm, Germany, specializes in web-based transport-management software. Transporeon is a transport-management software provider that is also headquartered in Ulm.

Riverside expects the acquisition to strengthen Transporeon by allowing it so accelerate growth. The private equity firm, headquartered in New York and Cleveland, won Mergers & Acquisitions Mid-Market M&A Award for private equity firm of the year for 2012

In December, Riverside acquired Hytec Geratebau GmbHto add to portfolio company Keymile. In November, Riverside bought Y. International, a Tokyo-based bicycle retailer.