US-based distributed ledger technology producer Axoni has boosted its series A round to more than $20m following an investment by financial services firm Citi.

The precise amount Axoni has raised has not been revealed, though a regulatory filing made at the time of the round’s first close in December 2016 shows Axoni was seeking a total of $20.5m.

The round’s $18m first tranche was co-led by financial services firm Wells Fargo and Euclid Opportunities, the strategic investment division of…