Companies such as Apple and General Motors gave up crucial company information to social engineers during the annual Capture the Flag contest at Def Con. Apple, Boeing, Chevron, Exxon, General Dynamics, General Electric, General Motors, Home Depot, Johnson & Johnson and Walt Disney Corp. Competitors had two weeks to gather open source intelligence data prior to DEF CON, excluding onsite visits or phishing attempts. Apple fared the worst in the contest, followed by General Depot and Home Depot. Details on specific vulnerable areas were not made public to the target companies, but are available to the public.
Source: https://threatpost.com/major-corporations-fail-to-defend-against-social-engineering/102733/