Under the deal announced Wednesday, Oracle will not pay for the company up front but will enter into an earnings-sharing agreement. The deal is expected to be concluded next month.
"The combination is expected to help Oracle deliver a complete line of storage products that runs Oracle software faster and more efficiently," Oracle said in a statement.
The software giant, founded by Ellison in 1977, added that the negotiations over the acquisition were carried out by an independent committee.
Pillar Data Systems is a privately-held company based in San Jose, California that boasts nearly 600 customers across 24 countries.
The latest deal follows Oracle's acquisition of Web management company FatWire Software earlier this month, a deal expected to be concluded in the middle of this year.
Fatwire was founded in 1996 and is based in Mineola, New York. It boasts 500 customers in 11 countries in sectors including financial services, media, technology, manufacturing, the public sector, retail and health care.
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