Google also owns http://duck.com and points it directly at Google search, which consistently confuses DuckDuckGo users.
DuckDuckGo was founded in 2008. According to a Security Trails domain record search,
duck.com was transferred from Level 3 Communications/On2 Technologies to Google in November 2010, about a year after On2 was acquired by Google. I’m having a hard time understanding why Google would use this domain for this purpose for any reason other than to bully confused DuckDuckGo searchers, as it appears to have redirected to
google.com ever since unlike, say,
Update: Google is now showing an intermediate page that offers to redirect visitors to DuckDuckGo and provides some context about why they own the domain.