German chemical and pharmaceutical giant Bayer recently agreed to pay over $10 billion to settle tens of thousands of claims that its weed killer Roundup caused cancer (Roundup Maker to Pay $10 Billion to Settle Cancer Suits).

The deal is one of the largest legal settlements in United States history, involving agreements with 25 different law firms for widely varying amounts. “It’s rare that we see a consensual settlement with that many zeros on it,” said Stanford University Law School professor Nora Freeman Engstrom.