I saw a question regarding the acceptability of stacking chip components at this forum posted in 2000. Unfortunately no one could cite any applicable IPC sections at that time. I am now able to find that this is acceptable per IPC-A-610D, Section 18.104.22.168.3 and IPC-A-610E, Section 22.214.171.124.
What I still don't know is how many chip capacitors can be stacked - can I stack two components (total of three parts) or only one (total of two parts)? There doesn't seem to be a limitation based of the reference tale 8-2.
I would appreciate any insight that anyone can provide.