The Delaware Court of Chancery on Monday allowed Fresenius SE to walk away from its planned $4.3 billion deal to acquire generic drugmaker Akorn Inc., ruling that a series of regulatory compliance issues at Akorn had allowed Fresenius to terminate the merger.

The post-trial ruling, from Vice Chancellor J. Travis Laster, was the first in Delaware to find that a series of missteps amounted to a “material adverse change” in a seller’s business that justified a buyer withdrawing from a merger.