San Diego software developer Accelrys Inc. has acquired the privately held ChemSW Inc., paying about $15.3 million in cash to ChemSW’s shareholders, Accelrys said.

In addition, ChemSW executives may be entitled to receive up to $2 million based on certain operational milestones during the first two years following the acquisition.

This is Accelrys’ latest acquisition — following VelQuest (January 2012), Aegis (October 2012) and Vialis (January 2013).

Accelrys (Nasdaq: ACCL), a $508 million market cap company, develops software to help optimize laboratory research processes — allowing scientists to access, organize, analyze and share data. The Fairfield-based ChemSW develops software that helps labs adhere to environmental safety regulations.

— Meghana Keshavan