PDB samplers employ patented technology (U.S. patent number 5,804,743), the user is required to purchase commercially produced samplers from a licensed manufacturer or purchase a nonexclusive license for sampler construction from the U.S. Geological Survey Technology Enterprise Office at:
U. S. Geological Survey Technology Transfer Enterprise Office
Mail Stop 211, National Center
12201 Sunrise Valley Drive
Reston, Virginia 20192
Phone: 703-648-4403
Fax: 703-648-4408