Both WMI and WMIH owned 100% of the "Equity Interests" in WMB and WMIIC respectively. In WMIIC's case, 100% Equity ownership of a 25% Cert Participation is complete ownership.
The terms "Equity Interests" and "Stock" were used interchangeably to signify full ownership of WMB and WMIIC, even though no actual "Stock" was ever issued for either.
In addition, without the Asset component, owning 100% Equity in an Asset-less company is worthless, as evidenced in WMI/WMB scenario.
All IMOOC