by Michael Malvick (Greatland Reviewer)
Each time a geocacher creates a cache page to submit for review and publishing, s/he checks a box next to the statement 
A basic tenet of the Geocaching Hiding Guidelines is “by submitting a cache page, you agree that you have all necessary permissions from the landowner or land manager to hide your geocache at that location.”
So, how do you determine that? One way NOT to do that is place a geocache in an area just because another cacher hid a geocache there without verifying that cacher got necessary permission. This is because the first cacher may not, in fact, have sought and received permission, or, permission conditions and/or land parcel boundaries may have changed.
Your first stop can be the Regional Geocaching Policy Wiki which lists all the KNOWN locations caches can be placed, required permits, and areas where caches are prohibited. The Wiki is maintained by Geocaching HQ and the Community Volunteer Reviewers. If you become aware of an area where caching is or is not explicitly allowed in Alaska or Hawai’i that does not appear in the Wiki, please let Greatland Reviewer know through his profile’s e-mail or message links.
The Wiki also contains links to downloadable GPX format boundary files to use with Google Maps, GoogleEarth, Garmin Basecamp, and many other free mapping applications which allow overlays of the land parcel boundaries and geocaching pocket query GPX format files. Also included are links to several borough Geographic Information Systems (GIS) that include land ownership information which is useful for determining private versus public status.
Portable tools that work with Android and iPhones include the Acres and onX applications, which are available at different subscription levels.
Even more “how to” information can be found in the GeocacheAlaska! Eduvent Library. It is now easier than ever to know who owns or manages the land where you are standing with all the available online and application tools.
Make certain you know before you hide a cache and get turned back by the Reviewer or later have your cache archived upon the request of a land owner or manager who does not want a geocache on their property. If permission is received, get the permission in writing to document the permission in the event of ownership or management change. If an agreement is not confirmed in writing, it becomes hearsay in the future.
For more resources on researching land ownership, and how to be good supporters our local reviewer, check out the slide deck from the recent Reviewer Night eduevent: