In addition to the company sale, MarketAxess says selling shareholders will also offload an additional six million common shares, for a total offering of nine million common shares.

MarketAxess filed with the US Securities and Exchange Commission for a $150 million IPO in mid-February.

The company, which is owned and controlled by a collective of nine bond dealing firms, says the proceeds from the issue will be used for general corporate purposes, including working capital and capital spending, with some of the cash earmarked for business expansion "through strategic alliances and select acquisitions".