From The Atlanta Kosher Commission: O/V Hashkacha from St. Louis
The O/V symbol, out of St. Louis, is nearly identical to the symbol used to identify a product as vegan. This has caused much confusion, so the Vaad Hair of St. Louis is modifying its kosher symbol. The new logo will feature an OVK inside an oval.
Kashrus Conscience – 2018 West Coast Shopping and Dining
From The O/U: Abu Lafia

The O/U does NOT certify Abu Lafia pita. Some bags are printed with an unauthorized “O/U Pas Yisroel” symbol.
From The O/U: Tone It Up Marine Collagen

The O/U does NOT certify Tone It Up Marine Collagen. Some containers bear an unauthorized O/U symbol.