Last month, BuzzFeed laid off more than 220 employees, or 15 percent of its work force. On Tuesday, employees at the company’s news division responded with the announcement that they planned to form a union.

“It’s not all fun and memes,” the organizing committee said in a statement. “Our staff has been organizing for several months, and we have legitimate grievances about unfair pay disparities, mismanaged pivots and layoffs, weak benefits, skyrocketing health insurance costs, diversity and more.”

More than 40 of those who lost their jobs in the recent layoffs worked in the company’s bureaus in New York, Washington, San Francisco and Los Angeles. The cuts included all seven members of the BuzzFeed News national desk and six members of its nine-person national security team

BuzzFeed’s revenue grew by more than 15 percent in 2018, but that gain wasn’t enough to stave off the decision by its founder, Jonah Peretti, to reduce the number of employees. In an email to the staff before the firings, Mr. Peretti wrote, “Unfortunately, revenue growth by itself isn’t enough to be successful in the long run.”