The Minnesota-based conglomerate 3M leads the pack of the biggest U.S. exporters, according to an analysis conducted by Panjiva Inc., a research firm that provides international trade data. Panjiva analyzed export data from 2009 to 2012 to develop its rankings, which are based on exporters' number of shipments.

1. 3M
2. Tyson Fresh Meats Inc.
3. DuPont
4. Dow Chemical Co.
5. Eastman Chemical Co.
6. Kimberly-Clark Global Sales
7. Union Underwear Company (Fruit of the Loom)
8. America Chung Nam
9. Cellmark, Farmland Foods (tie)

Source: Panjiva Inc.