Originally Posted by Groundpointfife

Here are the guidelines:

PIC (Pilot In Command) = Any time you signed for the plane as aircraft commander
or solo including all instructor time.
SIC (Second In Command) = Any time you acted as second in command and/or didn't sign for the plane.
This DOES include dual/student time.
Instructor = Only the time you logged as an instructor, regardless of the time being reported in PIC.
Instructor time is PIC time. It belongs in both columns.

https://aa.pilotcredentials.com/index.php?a=questions

There you go. Answered and with a link to the source.