2.1.1857 Part 4 Section 19.4.2.3, Anchor (Anchor)

a.   The standard describes the TopRow and BottomRow values of the Anchor element in terms of a column.

Office considers the TopRow and BottomRow values of the Anchor element in terms of the row, rather than column, and considers the top-most row to be 0.

b.   The standard indicates that the BottomOffset value of the Anchor element is the offset of the object's bottom edge from the bottom edge of the bottom anchor row.

Office considers that the BottomOffset value of the Anchor element is the offset of the object's bottom edge from the top edge of the bottom anchor row.

c.   The standard indicates that the Anchor element is specified using a comma-separated list of values, but does not require constraints on the list.

Office requires the string value of the Anchor element to be a comma-delimited list of 8 non-negative integers.