First Printing, pp.122-123 (Property Trait & Property Trait Table); pp.126-127 (Title Trait & General Title Table); p. 353 (Marquis & Duke).
The problem is an inconsistency between what the higher levels of Property can gain a character when "tied" to noble Titles.
According to p.126,127 & 353, a 10TP Title corresponds to a Duke, who's supposed to rule "an often sizable territory that can range from a single important world to a collection of border worlds" (p.353, that sets the TP cost for this level of Property at 10TP). A 9TP Title corresponds to a Marquis, whose power "ranges from a continent to a border world, or sometimes influence over several border/Periphery worlds." (again, p.353, that sets the TP cost of this level of Property at 8TP).
However, according to pp. 122-123, those same levels of the Property Trait buy a character a bit less than what we read on p.353. In particular:
8TP buys "a small continent or large islands".
9TP buys "a continent"
10TP buys "a small moon or multiple continents"
11TP buys "a planet".
So a Duke (a 10 TP Title) would not be able to control even single planet (11TP Property, which according to p.123 requires an 11TP Title), never mind an "important world or a collection of border worlds".