Citigroup has filed a claim with Nasdaq OMX Group, seeking adequate compensation from the exchange operator over the losses it sustained during the launch of Facebook IPO on 18 May 2012.
Many market players and broker dealers along with Citi claimed that they lost approximately $500m, due to some software glitch during the IPO launch.
Nasdaq had offered $62m compensation to cover the losses, which was not accepted by UBS, Citigroup and other major financial firms, saying it is inadequate.
In February, the exchange group was reportedly negotiating with the US Securities Exchange Commission (SEC) over a potential settlement related to poor handling of the offering.
Citi is also mulling to initiate legal proceedings, if it fails to receive adequate compensation, according to media sources.
In May 2012, Reuters reported that Citi lost approximately $20m during the launch of public offering of social media conglomerate.
UBS already filed an arbitration demanding compensation for more than $350m losses, it sustained due to the gross negligence of the exchange operator.