Internal data shows that African-Americans face a “glass ceiling” at CNN, according to a class-action lawsuit filed on Wednesday.

The suit, filed in Atlanta, draws heavily on an internal HR Diversity Trends Report, which showed that men of color consistently received the lowest ratings on performance reviews. The report also found that the upper ranks of management were substantially less diverse than the company as a whole.

Though CNN and its parent, Turner Broadcasting, which is owned by Time Warner, have made efforts to diversify, the class-action suit alleges that once they are hired, African-Americans are held back by an unfair and arbitrary promotions process. The suit alleges that African-Americans must wait much longer for promotions, and make less than their white counterparts.

The class-action case arose from an earlier lawsuit filed on behalf of DeWayne Walker, an African-American employee who sued CNN earlier this year, saying he had been passed over for promotion nine times.

Attorney Daniel Meachum said that following the filing of that lawsuit, “we have uncovered stories involving abuse of power, nepotism, revenge, retaliation, and discrimination.”

The class-action suit names two additional plaintiffs: Celeslie Henley and Ernest Colbert. Henley, an administrative assistant, said she was required to work 12-13 hour shifts while white administrative assistants worked 8-hour days. When she complained to HR about the excessive workload, she was fired, according to the suit. Colbert, a mid-level manager who still works at TBS, alleged that he was only promoted twice in 19 years. He also contended that he worked twice as hard as his white counterparts while being paid thousands less.

CNN declined to comment.