Formerly, through PLUS Stock Exchange plc (PLUS-SX), PLUS also operated two primary markets:

PLUS-SX was acquired by ICAP on 21 June 2012 (see ICAP Securities & Derivatives Exchange (ISDX)). On 30 December 2016, ISDX was renamed NEX Exchange. Following the acquisition of NEX Exchange Limited by Aquis Exchange PLC, NEX Exchange changed its name to Aquis Stock Exchange (AQSE).