Zenefits, an insurance startup that is no stranger to difficulties, is laying off more than 400 workers. That's a big deal: those employees account for 45 percent of its workforce, according to BuzzFeed News, which broke the news.

The layoffs are just the latest cuts at the embattled company. They will largely hit workers in San Francisco as well as Arizona, according to reports.

What the company is saying: "This has been planned for some time and is the result of a lot of hard work over the past year to improve our products and service and make the operations of the company more efficient," a company spokesperson said in a statement.

The bigger picture: This is not the start of Zenefits' problems. It has grappled in recent years with revelations that it was skirting legal requirements and the related departure of its co-founder. The company appointed a new CEO just last week.