2.1.262 Part 1 Section 17.8.3.1, altName (Alternate Names for Font)

a.   The standard describes the altName element as a set of alternative names given as comma-delimited list.

Word does not split values on commas or anything else; instead, it treats the entire value as a single alternate font name.

b.   The standard does not limit the length of the value of the val attribute.

Word restricts the value of this attribute to be at most 31 characters.

c.   The standard states that the value of the altName element does not change when resaving a document.

Word removes the altName element for system fonts, keeps it for other fonts the first time they are loaded in the session, and reverts them to the previous value for subsequent times they are loaded in the session.

d.   The standard states that the value of the altName element does not change when resaving a document.

When Word resolves an unknown font, it changes the value of the altName element to the font to which it was resolved, whether altName had a value before or not.