Google, the company that wants to make the world’s information accessible, says the race and gender of its work force is a trade secret that cannot be released.

So do Apple, Yahoo, Oracle and Applied Materials. These five companies waged an 18-month Freedom of Information battle with the Mercury News, convincing federal regulators who collect the data that its release would cause “commercial harm” by potentially revealing the companies’ business strategy to competitors. A sixth company, Hewlett-Packard, fought the release and lost.

But many of their industry peers see the issue differently. The Mercury News initially set out to obtain race and gender data on the valley’s 15 largest companies, and nine — including Intel, Cisco Systems, eBay, AMD, Sanmina and Sun Microsystems — agreed to allow the U.S. Department of Labor to provide it.

“There’s nothing to hide, in our view,” said Chuck Mulloy, a spokesman for Intel, which contacted the Mercury News to share its employment data after learning of the newspaper’s federal FOIA request filed in early 2008. “We just felt that we’re very proud of the (diversity) programs we have in place and the efforts we put forth, and we don’t have any trouble sharing it.”

Experts in the area of equal employment law scoffed at the idea that public disclosure of race and gender data — for example, the number of black men or Asian women in job categories such as “professionals,” “officials & managers” and “service workers” — could really allow competitors to discern a big tech company’s business strategy. A bigger issue, they said, is the social cost of allowing large, influential corporations to hide their race and gender data.

“One of the main ways that we track how society is doing in terms of race relations, in terms of eliminating discrimination, in terms of promoting diversity, is by looking at statistics,” said Richard Ford, a Stanford University law professor who is an expert in civil rights and anti-discrimination law. “But if we can’t get the data, we can’t know if it’s a problem or not.”

John Sims, a law professor at the University of the Pacific and an expert in FOIA law, called the objections of Google, Apple and other companies “absurd.”

“The whole debate on affirmative action is based on the question, ‘Is racial discrimination a thing of the past, or is it still going on?’ ” Sims said. “These companies are very interesting to look at, because they are new and they are not just in the rut of what they were doing 50 years ago, because they didn’t exist 50 years ago.”

The Labor Department data ultimately obtained by the Mercury News shows that while the collective work force of 10 of the valley’s largest companies grew by 16 percent from 1999 to 2005, an already small population of black workers dropped by 16 percent, while the number of Hispanic workers declined by 11 percent. By 2005, only about 2,200 of the 30,000 Silicon Valley-based workers at those 10 companies were black or Hispanic.

In addition, among the roughly 5,900 managers at those companies in 2005, about 300 were either black or Hispanic — a 20 percent dip from five years earlier. Women slipped to 26 percent of managers in 2005, from 28 percent in 2000.

Companies such as Google and Apple are particularly crucial to study, Ford said, because many of the nation’s civil rights laws were written in the 1960s for a different workplace than the information-driven jobs of today.

The Mercury News initially asked the Labor Department to release so-called EEO-1 race and gender data for the 15 largest companies ranked by sales in the newspaper’s SV150 Index.

Following an appeal lodged by the Mercury News against the six companies that objected, the Labor Department released Hewlett-Packard’s data after the company failed, government lawyers said, to provide a detailed objection “when we requested its views.”

But the Labor Department accepted arguments filed by lawyers for Google, Apple, Yahoo, Oracle and Applied Materials that release of the information would cause commercial harm. The department declined to share the text of the detailed arguments made by the companies.

“Such data can demonstrate a company’s evolving business strategy,” William W. Thompson II, an associate solicitor with the Labor Department, wrote in the agency’s notification of its final action.

“The companies have articulated to us that they are in a highly competitive environment in which less mature corporations can use this EEO-1 data to assist in structuring their business operations to better compete against more established competitors.”

Google recently announced that it donated $8 million over the last two weeks of 2009 to help underrepresented minorities follow careers in technology, including the donation of laptops to more than 600 high schools, and donations to groups such as the National Society of Black Engineers.

Still, the company declined to release any racial or gender breakdown of its 20,000 workers.

“As we’ve previously said, we don’t release this information for competitive reasons,” a spokeswoman said.

Contact Mike Swift at 408-271-3648. Follow him at Twitter.com/swiftstories and view his Google+ profile.