A more thorough explanation:

in fieri (in fI-ə-rI), adj. [from Latin in "in" + fieri "to be done"]

(Of a legal proceeding) that is pending or in the course of being completed.

1. The lawsuit is in fieri and will be heard in court next month.

2. The contract negotiations are in fieri and we hope to reach an agreement soon.

3. The investigation is in fieri and we cannot comment on it at this time.

These examples illustrate the definition of in fieri as a legal proceeding that is pending or in progress. In example 1, the lawsuit is still ongoing and has not yet been resolved. In example 2, the contract negotiations are still in progress and have not yet been finalized. In example 3, the investigation is still ongoing and no conclusions have been reached yet.