Akorn Inc. shares dropped about 47% in Monday premarket trade after a Delaware court ruled in favor of Fresenius SE & Co. , which has sought to end a $4.3 billion merger. Akorn shares have been halted, while Fresenius shares rose 8.5% in heavy Monday morning trade. The Germany-based Fresenius previously terminated the merger "due to Akorn's failure to fulfill several closing conditions," the company said in a Monday statement. "An independent investigation initiated by Fresenius had revealed, among other things, material breaches of FDA data integrity requirements relating to Akorn's operations." The merger had been agreed to in April 2017, and Fresenius said earlier this year that it was ending it. Akorn subsequently sued in late April. The Lake Forest, IL-based generic drugmaker said that it was disappointed by the court's decision and plans to appeal. Akorn shares have dropped nearly 22% over the last three months, and Fresenius shares have slumped 0.2%. The S&P 500 has risen 7.8% in the same time, and the Dow Jones Industrial Average has risen 9.7%.