I was referring to crawlers that build indexes for search engines to use. DuckDuckGo does have a crawler—DuckDuckBot—but it’s only used for fetching favicons and scraping certain sites for infoboxes (“instant answers”, the fancy widgets next to/above the classic link results).
DuckDuckGo and other engines that use Bing’s commercial API have contractual arrangements that typically include a clause that says something like “don’t you dare change our results, we don’t want to create a competitor to Bing that has better results than us”. Very few companies manage to negotiate an exception; DuckDuckGo is not one of those companies, to my knowledge.
So to answer your question: it’s irrelevant. “html
For the record, Google isn’t any different when it comes to their API. That’s why Ixquick shut down and pivoted to Startpage; Google wasn’t happy with Ixquick integrating multiple sources.