In an effort to fend off so-called activist investors, Hewlett-Packard is ramping up its defenses by hiring banking giant Goldman Sachs to help devise a strategy against potential shareholder “activism,” according to media reports.

Activist investors with enough shares could demand drastic changes at the company, the Wall Street Journal reported this week.

“HP has felt vulnerable to possible activist investor pressure amid questions about the company’s performance and strategic direction, the people said. The concerns intensified earlier this month when Leo Apotheker was ousted as chief executive and replaced by Meg Whitman,” the Journal said, citing people “familiar with the matter” who were not named in the report.

Asked about the report, an HP spokesman said the company “has long-term relationships with a large number of investment banks,” according to the Journal.

On Sept. 22, after only 11 months on the job, the board of directors of Hewlett-Packard replaced troubled CEO Leo Apotheker with former eBay CEO and California candidate for governor Meg Whitman, TechZone360’s Peter Bernstein reported.

However, instead of doing the obvious, i.e., announcing that the board was replacing Apotheker with Whitman, the board let the change become a rumor and then let the rumor linger. TMC CEO Rich Tehrani is giving Whitman 12 months in the job at best.

Adding insult to injury, previous to the leadership change announced last week, shares of HP plummeted after the company announced many stunning changes in August – including that it may spin off its PC business. PC sales represent about one-third of HP’s business, TechZone360 reported.

HP’s stock dropped nearly $7 on Aug. 19, some 23 percent, to about $23 a share, according to news reports. The stock fell 15 percent in pre-market trading. MarketWatch said HP stock has dropped 30 percent during 2011.

Apotheker was named CEO last year. A European and a company “outsider” – rather than someone who had roots in Silicon Valley – Apotheker’s selection came as a surprise to several analysts, TechZone360 reported.