To reproduce: create articel with author with three first initials, like:
LastName, A. B. C.
Then export to MS Office. In the Sources.xml it will incorrectly read:
<b:last>C.</b:last>
<b:middle>B.</b:middle>
<b:first>A.</b:first>
It works correctly if there are only two initials (like LastName, A. B. )
Same behavior when exporting to MODS Format.
The result of exporting an entry with the author LastName, A B C is:
. . .
<namepart type="family">C</namepart>
<namepart type="given">A B</namepart>
. . .
will take care of that
Sent a patch to fix this (# 3461164).