The storage software industry has seen its first quarterly sales decline after more than five years of solid growth, according to a report from market researcher IDC.

First-quarter 2009 revenue for the industry sank 5.2 percent to $2.8 billion from the previous year. The slump has impacted several key vendors, including Hewlett-Packard, EMC, and IBM, all of which sell storage software to enterprise clients.

"The combination of the normally slow first quarter for most companies with the contin...