Pure Storage, a flash player that aims to disrupt the business of storage arrays, has received a $40 million fourth round of funding, led by Index Ventures.

The Mountain View, Calif.-based company, founded in 2009, claims to offer an enterprise flash array that can drive down the cost of server storage. Pure Storage’s technology works by maximizing the amount of data that can be stored on solid state drives. The company uses a number of methods to reduce the amount of space on a hard disk, including deduplication and additional compression.

Pure Storage faces strong competition from XtremeIO, an Israeli flash company recently acquired by EMC.

At VMworld, an upcoming virtualization and cloud computing conference, the company will announce an update to its flagship product, FlashArray, which it claims will rival XtremeIO. The new features will tightly integrate with VMware, so it should come as no surprise that Helen Greene, cofounder and CEO of VMware, is a participating investor in the company’s Series D.

Pure Storage said it would use the funds to expand its operations to Europe and continue to scale operations in the U.S.

The latest funding round was led by Mike Volpi at Index Ventures, with participation from Greylock, Redpoint, Sutter Hill, angels from VMware and DataDomain, and others.