With this paradoxical partial decision, the jury has left the case very much in the air, and Google has already moved for a mistrial.

On Monday, as the Google-Oracle case entered its fourth week, a jury ruled that Oracle has proven that Google infringed the overall structure, sequence, and organization of copyrighted works of 37 APIs used by the Java platform. In building Android, Google created a new version of the Java platform known as the Dalvik virtual machine, and this mimicked the Java APIs, or application programming interfaces, which are essentially a way for a Java application to talk to the platform.

But the jury was unable to reach a decision on whether Google’s Java clone constituted “fair use.” A fair use decision would let Google off the hook.

After receiving the verdict, Judge William Alsup told the jury it would not have to answer the fair-use question, and Google immediately asked that the judge declare a mistrail, arguing that precedent says you can’t decide on infringement without deciding on fair use. Google will file a brief and expand on this argument tomorrow.