No, it uses bing + a little secret sauce, as I understand it.
Edit: "Link results are API driven, though top links may come from other sources. Link sources include: Bing, Yahoo, Yandex, Blekko, WolframAlpha, and many others."[1]
"DuckDuckGo gets its results from over one hundred sources, including DuckDuckBot (our own crawler), crowd-sourced sites (like Wikipedia, which are stored in our own index), Yahoo! (through BOSS), Yandex, WolframAlpha, and Bing. For any given search, there is usually a vertical search engine out there that does a better job at answering it than a general search engine. Our long-term goal is to get you information from that best source, ideally in instant answer form."[2]
Edit: "Link results are API driven, though top links may come from other sources. Link sources include: Bing, Yahoo, Yandex, Blekko, WolframAlpha, and many others."[1]
"DuckDuckGo gets its results from over one hundred sources, including DuckDuckBot (our own crawler), crowd-sourced sites (like Wikipedia, which are stored in our own index), Yahoo! (through BOSS), Yandex, WolframAlpha, and Bing. For any given search, there is usually a vertical search engine out there that does a better job at answering it than a general search engine. Our long-term goal is to get you information from that best source, ideally in instant answer form."[2]
1. http://highscalability.com/blog/2013/1/28/duckduckgo-archite...
2. https://duck.co/help/results/sources