[Latios]

I think I am getting close how to fix it:

I have modified the code template like this:

{author_sort:'contains($,",",strcat(uppercase(list_item($,0,",")),", ",list_item($,1,","),", ",list_item($,2,","),", ",list_item($,3,",")),uppercase($))'}

And this is the new outcome:

When Author sort's metadata shows: Smith, Sam & Dallas, Ken
...applying the code you gave me, comes up like: SMITH, Sam & Dallas, Ken

For example, with more than two:
When Author sort's metadata shows: Ronald, Alex & Chan, Liu & Tiffany, Megan
...applying the code you gave me, comes up like: RONALD, Alex & Chan, Liu & Megan, Tiffany

The only thing missing now is to make the second and following last name's author into capital letters.

what am I missing?