When Carly Fiorina counters criticism of her rocky leadership of Hewlett-Packard, she often invokes an unlikely defender: Tom Perkins, the Silicon Valley venture capitalist who voted in 2005 for her termination.

"The man that led my firing, Tom Perkins, just took out a full-page ad in the New York Times to say he was wrong, I was right,” she proclaimed last month during the Republican debate. The super PAC backing her campaign paid for the prime spot, where Perkins commends Fiorina’s “strength of character” in 700 words and claims her firing was “a mistake.”

The endorsement has spurred skepticism among some former board members who also voted to dismiss Fiorina, revealing residual anger from a decade-old ouster that rocked the technology world.

They say Perkins changed his tune only to attach himself to a rising political star, and that he’s now attempting to rewrite corporate history.

“He simply did not think she had the tools in her tool set to run [Hewlett-Packard],” said George Keyworth, a former board member. “He must think that running a country requires a different skillset than running a company."

Fiorina and Perkins clashed routinely during her tenure, Keyworth said: She thought Perkins was trying to run the show, and he questioned her technical savvy. He first resigned in 2004, three years after joining the board during HP’s marriage to Compaq Computer. Fiorina forced him out, the directors recall, but Perkins said he’d simply reached retirement age.

When he returned to the board in 2005, directors said it was because they needed an extra vote to oust Fiorina. Keyworth traveled to Plumpton Place, Perkins’ moated mansion in East Sussex, England, to ask him back. In his first official meeting in the renewed role, Perkins moved to fire Fiorina.

(Keyworth resigned in 2006 after an internal investigation discovered he’d leaked sensitive company information to a reporter).

Fiorina's campaign declined to comment for this story, but she wrote in her memoir Tough Choices that she was “appalled by (Perkins’) reemergence” on the board and agonized over questions after her firing, including, “What if Tom Perkins hadn’t returned?”

Perkins, however, denies engineering the ouster. He said in an interview this week: “I never wanted to fire Carly, but I wanted there to be peace on the board.” (He also denied secretly discussing the ouster weeks before Fiorina’s fate was decided in the boardroom vote).

Lucille Salhany, a board member from 2002 to 2011, remembers it quite differently: “There was not a question: if [Perkins] didn't really want to fire her, it never would have happened.”

Salhany, a prominent media executive, has a theory about his apparent change of heart: “Maybe Tom likes the national stage,” she said. “Maybe Tom is looking to be more involved in national politics than just limiting himself to Silicon Valley. “

Roy Verley, a 21-year HP employee and longtime chief corporate spokesman, said Perkins’ support for Fiorina should not shock anyone who follows his technicolor career. “Tom Perkins has a reputation for playing both ends,” he said, “and doing anything to aggrandize Tom Perkins.”

After her firing, Fiorina wrote in her memoir, Perkins mailed her a letter wishing her luck on her next career move and saying, “If it should be to seek an elected office, I would be honored if you would let me participate on the fundraising side.”

In public, however, he continued to excoriate her, saying in interviews during his 2007 book tour that HP employees sang, “Ding, Dong, the Witch is Dead” after her firing and adding, “She still doesn’t understand that she bears some responsibility for that. It’s amazing.”

Under Fiorina, HP shares fell more than 50 percent, far worse than those of competitors such as IBM and Dell. Amid a high-profile merger with Compaq Computer, more than 30,000 workers lost their jobs at a six-decade-old company that had never previously endured such downsizing.

The year  Fiorina left, profits were $1 billion less than when she started, even though the company was twice the size. She has blamed the dot-com bust and a dysfunctional board. Several high-ranking executives who reported to her say the company desperately needed the dramatic change in direction that she provided to avoid slipping into obscurity.

In past interviews, Fiorina has called Perkins one of the chief architects of a dismissal she felt was personally damaging and cruel. “The way this was handled was heartless in some ways and disrespectful in other ways,” she told 60 Minutes in 2006. “Maybe they took great pleasure in seeing me beat up publicly for weeks and weeks and weeks, I don’t know.”

Neither she nor her supporters, though, have hesitated in holding up Perkins as a chief defender.

In May, he donated $25,000 to Carly for America. Three months later, the super PAC paid for the national ad extolling Perkins’ views on “The Truth About Carly,” which the New York Times said cost about $140,000.

Fiorina’s backers have hung their platform on parading out former HP employees who now defend her record. Bill Mutell, a former HP senior executive, has defended Fiorina in the press, telling CNN earlier this year, “CEOs aren’t there to have coffee in the cafeteria with employees and to yuk it up.”  (In Mutell’s biography with the College of William & Mary’s business school, where he is an executive partner, he is now listed as a Fiorina “strategy adviser").

Perkins, once an HP insider of the highest order, remains the star witness. “I was in the room for many of the decisions she made,” he wrote in the Times ad. “I can attest to the strength of Carly’s leadership, the accuracy of her vision and the quality of her management.”

He worked at HP before he founded the venture-capital titan now known as Kleiner Perkins Caufield & Byers. He sat on the Compaq board and enthusiastically supported the 2001 merger with HP.

He rarely mentions now butting heads with Fiorina over how to run the new mega-firm  — or his previous angst at her pushes to edge out high-level executives like Peter Blackmore, formerly head of sales at Compaq.

News about Perkins’ personal life occasionally eclipses his business legend in Silicon Valley.

He married romance novelist Danielle Steel in 1998 and split with her in 2002. He wrote and dedicated a book to his ex-wife called Sex and the Single Zillionaire, further fueling his reputation as an unapologetically rich playboy.

So did his 289-foot sailboat, the Maltese Falcon, which one magazine called “a big boatload of ego.” In a 60 Minutes segment called “Captain of Capitalism,” Perkins revealed a series of lettered flags on the boat spell out: “Rarely does one have the privilege of witnessing vulgar ostentation displayed on such a scale.”  He told the reporter, “Do I have an ego? Yes. Is it big? Yes.”

More recent interviews have stirred outrage. Perkins’ radical views on wealth went viral in January 2014 after he wrote a widely criticized letter to the Wall Street Journal, comparing the “war on the American one percent” with the treatment of Jews in Nazi Germany. (The venture-capital firm he founded distanced itself from Perkins, saying it was “shocked by his views … and do not agree”).

The next month, Perkins said in a San Francisco speech that rich taxpayers deserve more votes than the poor, arguing, “You pay a million dollars in taxes, you get a million votes.”

In his interview with the Post, Perkins said he chose to become a vocal Fiorina supporter after “a long period of reflection.”

After her ouster, he said, they met at a restaurant in San Francisco and made up. He agreed to support her 2010 bid for Senate, a failed run against Barbara Boxer. That year, he told the Los Angeles Times, “Look where HP is now: the biggest computer company in the world."

Now, Perkins is planning a swanky fundraiser in San Francisco, date to be determined. He’s eager to clear the air for Fiorina, he said, whose image has been tarnished by baseless attacks.

In the Times ad, he wrote, “We are in the middle of a heated election, and often facts and the truth get lost in the heat of partisan rhetoric."

Alice Crites contributed to this report.

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