What does it mean when a software is called open-source for US-release only?

Question

I saw this answer about MarsGRAM, and when I clicked on the NASA software link to read about it I saw at the bottom of the page a blurb for EarthGRAM 2010, an atmospheric model for Earth with likely all kinds of insight beyond a simple scale heigh or scale height modified by temperature spherical model.

I was happy to see "open-source", as well as the easy-to-read and transcribe "FORTRAN" language.

But at the bottom it says "U.S. Release Only" and I am living overseas.

Question: What does it mean when a software is called open-source for US-release only? What are the rules exactly? Does this refer to the location of download, or of use, or to the citizenship of the person requesting the software?

So far I have not been able to find out what the restrictions really are. I've cycled through a few links but so far without initiating a request for the software, I am not sure how to view the restrictions on eligibility.

Answer 1

Here is what the NASA Software FAQ says:

The release type determines who can have a NASA software code. If you meet the access criteria for the code (as defined below), NASA can transfer the software to you. Release types:

General Public Release: For codes with a broad release and no nondisclosure or export control restrictions

Open Source Release: For collaborative efforts in which programmers improve upon codes originally developed by NASA and share the changes

U.S. Release Only: For codes available to U.S. persons only

U.S. and Foreign Release: For codes that are available to U.S. persons and persons outside of the U.S. (who meet certain export control restrictions)

U.S. Government Purpose Release: For codes that are to be used on behalf of the U.S. government by a federal agency or business/university under a federal contract/grant/agreement.

^{emphasis added}

In case that is not clear, here is the definition of a U.S. person from the University of Pittsburgh Office of Research:

U.S. Person (EAR Part 772 and ITAR 120.15) Pursuant to the EAR and the ITAR, a U.S. Person includes :

any individual who is granted U.S. citizenship; or

any individual who is granted U.S. permanent residence ("Green Card" holder); or

any individual who is granted status as a "protected person" under 8 U.S.C. 1324b(a)(3);

any corporation/business/organization/group incorporated in the United States under U.S. law;

any part of U.S. government.

You will note that the page for Earth-GRAM has a request link instead of a download link. That is how they check to ensure you qualify to receive the release.