Is it legal to copy and distribute DRG files?
In the case of USGS-derived DRG files, yes. The USGS has released all topographic maps of the United States into the public domain, including the digital versions (DRG’s). It is legal to copy and distribute these files as you wish. What may be confusing is that many vendors charge exorbitant fees to sell you a set of CD’s or DVD’s containing DRG files for a large area (typically a full state), but what they’re charging for is the cost to distribute those files to you, rather than the data itself. Additional information about the USGS’s position on copyrighted data and the public domain status of USGS topographic maps can be found here.
