Entering ‘OC’ will print ‘US’ in the US Source column. We do not plan to alter this, as IRS instructions repeatedly state "Do not enter “various” or “OC” for the country code." See IRS Schedule K-2 / K-3 Instructions pages 3, 4, 8, 12, and 23.

The IRS Schedule K-2 / K-3 instructions repeatedly advise that use the countries in the list of irs.gov/countrycodes. 

• The list does not include US - United States.
• The list does include OC - Other Country. 

The K-2/K-3 instructions for the country code says do not use "OC." However, the list of countries that the IRS instructions has mandated we use has "OC" as an option.  

• We are using "US" when "OC" is entered, since "OC" is not valid for Schedule K-2 / K-3(s).
• We are using "OC" as an input option because it is an option with the IRS published list: irs.gov/countrycodes
  • The existing foreign country code lists in the software generally includes "OC" and does not include "US" because the IRS would often invalidate most return types electronically with a “foreign country code” entered as US; Returns with US as a foreign country code would receive a schema validation error.