It baffles me that such egregious (alleged) racial discrimination occurs, especially in such a large company. While nobody expects their employees to engage in such conduct, preventative measures must be taken. For example, an employer may be able to avoid punitive damages in employment discrimination cases if they adopt anti-discrimination policies and conduct trainings on harassment and discrimination prevention. When an employer becomes aware of possible violations by their employees, they should exercise reasonable care to prevent and promptly correct any harassment.
The advice of an employment attorney is clearly recommended on discrimination and harassment issues, though the EEOC offers free publications with some general guidance for employers at its web site here.