McAfee chief executive David DeWalt wants to put to bed any notion that his position is merely one of "placeholder" at the security firm.

DeWalt took over as chief executive in April after a crippling stock option back-dating scandal saw the departure of previous chief executive George Samenuk and president Kevin Weiss.

Besides its legal woes, McAfee faces stiff competition in the enterprise and consumer security fields from long-time rivals Symantec and Computer Associates, along with the looming spectre of Microsoft's entry into the antivirus market.

Analysts have suggested that McAfee would be better off merging with a larger firm such as HP or Novell.

DeWalt, however, is angered by suggestions of a possible takeover. He told reporters at the company's Silicon Valley headquarters that McAfee is not being "shopped", and that he was not brought in from EMC in order to find a buyer.

"I was brought in to create shareholder value," he said. "There is a transformation that can be done here, and that is the greatest shareholder value I can create."

That transformation has included the replacement of several executives and a series of acquisitions, including this week's $350m deal to buy data protection firm Safeboot.

McAfee is also still involved in an ongoing effort to clear its name with the Securities and Exchange Commission.

"My strategy is to build the world's largest security company," said DeWalt, downplaying the importance of the two biggest hurdles: Microsoft and Symantec.

DeWalt asserted that much of Symantec's strength is inflated by its acquisition of storage firm Veritas.

Although Symantec's $18bn market cap dwarfs that of McAfee's $6.3bn, DeWalt contends that the pair are in a tight race for the position of the largest security vendor.

As for Microsoft, DeWalt claimed that McAfee gained more new business from the introduction of Windows Vista than it lost to Windows OneCare.

"I see Microsoft as a bigger partner than a competitor," he said. "The deployments of Vista require other security partners to make it secure and safe from zero-day attacks, which are a big problem."

In an increasingly consolidated security industry, DeWalt is banking that his company can thrive on its own rather than sell to a larger firm.

"It is an opportunity for us to grow at the expense of others who try to add a bit on and do not get it right," he said.

"Honestly, I think a lot of companies are going to look to a trusted security company as an adviser."