Oracle has received a statement of objections to its proposed acquisition of Sun from the European Commission but is in no mood to make concessions, which could further delay proceedings.
The concerns held by the EC are understood to centre on Oracle's long term plans for MySQL but the exact points have not been made public.
Nevertheless, Oracle resolutely defended its $7.4bn bid for Sun - which it claimed has been losing $100m a month while the EC drags its heels on approving the deal, and attacked the authorities' attitude.
"The transaction does not threaten to reduce competition in the slightest, including the database market," said Oracle.
"The Commission's Statement of Objections reveals a profound misunderstanding of both database competition and open source dynamics," it said, adding the whole point of open source was that it was not owned by anyone.
It pointed out the database market is competitive with eight players vying for business and that its application and MySQL were "very different database products".
Oracle also added that the US Justice Department concluded there was nothing anti-competitive about the deal, or any basis in law to veto the acquisition and the only losers by doing so were Sun customers.
"Sun's customers universally support this merger and do not benefit from the continued uncertainty and delay," it said.
Unsurprisingly given the tone of its response, Oracle will "vigorously oppose" the EC's objections and said the evidence supporting its position was "overwhelming".
"Given the lack of any credible theory or evidence of competitive harm, we are confident we will ultimately obtain unconditional clearance of the transaction," concluded Oracle.
The Department of Justice also lent its support to Sun, weighing in with its own comments: "There are many open-source and proprietary database competitors. The Division concluded, based on the specific facts at issue in the transaction, that consumer harm is unlikely because customers would continue to have choices from a variety of well established and widely accepted database products."
Some reseller partners have complained that the delay in getting approval is causing uncertainty among the customer base and want to see clarity sooner rather than later.