Dropbox is killing off unlimited storage in its business-focused Advanced plan following a surge in shady activity. It wrote in a blog post that as other services made similar changes to limit storage capacity, it has seen an increase in people using Advanced plans “not to run a business or organization, but instead for purposes like crypto and Chia mining, unrelated individuals pooling storage for personal use cases or even instances of reselling storage.”

While there will of course be legitimate outliers when it comes to unlimited storage plans, Dropbox says bad actors “frequently consume thousands of times more storage than our genuine business customers, which risks creating an unreliable experience for all of our customers.” It already has policies that prohibit abusive behavior, but the company says that creating a set of acceptable-use restrictions is unworkable. To that end, Dropbox is moving to a metered model.

The company will gradually move current users over to the modified Advanced plan starting on November 1st. Customers will get at least a 30-day heads up before Dropbox migrates them to the new policy.

Over 99 percent of customers on the Advanced plan each use less than 35TB of storage per license. Dropbox says those teams can continue to use however much storage they’re taking up at the time they get migration notification, plus an extra 5TB of pooled storage for five years with no price increase to their current plans.