ING to unload part of stake in ING U.S.Sep. 16, 2013 3:55 PM ET|By: Stephen Alpher, SA News Editor ING U.S. (VOYA -1.5%) isn't joining in the financial stock rally today after parent ING filed to sell part of its stake in the U.S. unit. ING currently owns 71% of the company. The size of the sale has not been disclosed. SEC Form S-1.