EMC has made a counter offer for Data Domain which is 20% higher than the $1.5bn bid tabled by NetApp last month.
Despite having a comparable deduplication portfolio, EMC's $1.8bn all-cash proposal launched late last night is bound to shake-up senior management at NetApp, who were bullish that their takeover would close mid-August.
The rival offer would provide Data Domain shareholders with "greater value and certainty", said EMC, and it was not subject to financing or due diligence contingency, as the vendor has reserve in the bank to fund it.
"Our substantially superior offer is a win-win for both companies," said EMC CEO Joe Tucci, who added that the acquisition would bolster its next-generation disc-based back-up and archive portfolio.
In late 2006, EMC acquired Avamar for around $165m, which makes up part of its deduplication strategy alongside OEM products from Quantum.
Tucci pointed out the deal will result "in a business larger than a billion dollars for EMC is 2010".
However, on top of a strong product portfolio, EMC could benefit from the addition of a management team that has executed well, said Eric Sheppard, programme director for European storage research at IDC.
"The idea that EMC would bid for a company with a comparable product offering means that it is also looking at Data Domain's management team," he said.