It also said it was changing its name to Icon Ventures.
Mullany was most recently chief executive of Sencha, an Icon-backed company that helps developers build web pages. He has also held senior roles at companies such as virtualization business VMware and networking business Opsware.
Icon has backed companies such as enterprise-security company FireEye, which raised $280 million in an initial public offering in 2013, and mobile-advertising business MoPub, which Twitter bought for $350 million in 2013.
In April, the venture firm raised $260 million for its latest fund.