Hydrox

Hydrox is a cream-filled cookie sandwich made by Leaf Brands. It originally launched in 1908, and was made by Sunshine Biscuits for over 90 years. Hydrox cookies have a sweet filling and a crunchy cookie shell.
The Oreo cookie, introduced in 1912, was inspired by the Hydrox. The Oreo eventually became more popular than Hydrox which resulted in Hydrox being thought of as a copy of Oreo. Hydrox was mostly closed in 1999 after Sunshine was bought by Keebler, which was later bought by Kellogg's.
In 2008, fans of Hydrox made thousands of phone calls and an online petition asking Kellogg's to make Hydrox again for its 100th anniversary. Kellogg's started making Hydrox again for less than one year. In September 2015, Leaf Brands began making Hydrox again with a new recipe. Leaf Brands filed a report with the US Federal Trade Commission in 2019. Leaf Brands claimed that the maker of Oreos, Mondelez International, unfairly put Hydrox products behind Oreo products on supermarket shelves.