Refer to the input text as context and select the correct relationship between 'Nomura Holdings' and 'Nomura Securities' from the available options.
Options: subsidiary, stock exchange, publisher, creator

He previously held senior roles at Nomura Securities Co, the brokerage unit of Nomura Holdings Inc. After he left Nomura, Saito served as CEO of the Industrial Revitalization Corporation of Japan, a now-defunct state-backed turnaround fund that invested in troubled companies.
subsidiary