The move comes after FXCM lost $225 million due to the surging Swiss franc, caused by the scrapping of a three-year-old cap on the value of the franc against the euro by the Swiss National Bank on Thursday.
The investment is in the form of a $300 million senior secured term loan, the companies said.
Leucadia owns investment bank Jefferies.
Reporting by Avik Das in Bengaluru; Editing by Sriraj Kalluvila
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