(CNNMoney) - How diverse are Silicon Valley's offices and executive suites? Activists have been trying for years to answer that question, but some of the industry's largest and most influential employers - including Apple, Google, Amazon and Facebook - closely guard that information.
Every U.S. company with more than 100 employees is required to file a one-page form each year with the Equal Employment Opportunity Commission, an independent federal agency. Called the EEO-1, the form categorizes U.S. workers by their race and gender.
It's a blunt and imperfect measurement tool, but it's also the only hard data available for tracking the diversity of corporate America.
CNNMoney filed a Freedom of Information request in August seeking EEO-1 data from 20 companies: The tech industry's 10 biggest firms by annual sales and 10 smaller but influential firms, including Facebook and Twitter. The EEOC denied the request in full, saying it is legally prohibited from releasing that information. CNNMoney later filed the same request with the Department of Labor, and is awaiting a response.