CEO Marc Benioff currently has a 90 percent approval rating from his employees, beating out rival and Oracle CEO Larry Ellison as well as SAP co-CEOs Jim Hagemann Snabe and Bill McDermott, according to figures from careers website Snabe and McDermott have an 80 percent approval rating under entries listed for "SAP," and a 67 percent rank among those posting reviews for "SAP America."

Ellison comes in at 78 percent, while IBM boss Sam Palmisano logged a 52 percent approval rating, edging out Microsoft CEO Steve Ballmer, who has 51 percent. HP's interim CEO Cathie Lesjack, who took over following Mark Hurd's controversial departure from the company last month, has a 59 percent thumbs-up. allows users to anonymously submit reviews of their workplaces, including data on job satisfaction and salaries. The site also features overall company ratings. IBM, Oracle and SAP were judged on average "OK" by employees, while and Microsoft workers offered a slightly higher assessment of "satisfied." HP staffers are on average "dissatisfied" with the company.

Glassdoor's figures shouldn't be viewed in the same light as a formal poll, as there are significant disparities in the number of ratings for each CEO and company. Moreover, reviewers' assessments of all the companies in the study run the gamut from gushing to scathing.

One called Benioff "a great leader and a brilliant marketer," but one disgruntled worker complained of "insufferable politics" and managers who employ "fear and ridicule" as motivation tools.

Similar dynamics are apparent in comments from Oracle employees. "Larry Ellison has always proved his critics wrong. He is a man with a vision and knows how to pick a management team," said one. But another contributor described Oracle as a stifling, fear-filled autocracy. "Anyone who dares to question Larry's omnipotence and omniscience becomes an immediate pariah."

SAP's showing is of particular interest given the management upheaval that occurred there earlier this year, when Snabe and McDermott replaced Léo Apotheker. Employee morale reportedly fell under Apotheker's fairly short time at the top. Many recent reviews for SAP are positive.

However, another suggested the company remains in a transition period, albeit on its way to better days. "In general, I believe that the senior management really, really want to build a better SAP. [But] despite the best of intentions, SAP continues to be mired in bureaucracy and indecision."

Meanwhile, Microsoft is "a toxic place to work" according to one review, while another declared it "an amazing company that genuinely cares for and respects its employees."

IBM and HP's reviews exhibit similar polarisation. "Don't work [at IBM] and if you work here now, leave ASAP," one warns. That advice doesn't jibe with the opinion of the reviewer who declared Big Blue "the only company I'd want to work for."

HP "continues to treat employees as disposable" and its board of directors "is inept," according to two writers. But those views contrast with a passel of declarations like the one calling HP "a great company to work for and a best-in-class leader in the 21st century."