For reporting actual, demonstrable GPS constellation errors only (not equipment or user issues):<p>mailto:pnt.office@gps.gov<p>via <a href="http:&#x2F;&#x2F;www.gps.gov&#x2F;support&#x2F;contact&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.gps.gov&#x2F;support&#x2F;contact&#x2F;</a><p>(Folks at shops like Trimble and Garmin already have contacts within their respective orgs, so employees should try to work with their channels where possible.)