epistemologue, your source holds that universals are entities:
"The phenomenon of similarity or attribute agreement gives rise to the debate between realists and nominalists. Realists claim that where objects are similar or agree in attribute, there is some one thing that they share or have in common; nominalists deny this. Realists call these shared entities universals; they say that universals are entities that can be simultaneously exemplified by several different objects; and they claim that universals encompass the properties things possess, the relations into which they enter, and the kinds to which they belong."
Underlining mine. That's from near the beginning of Chapter 1 in Objectivism and the Corruption of Rationality.
Will you grant the point now? If you are a realist, you are defending the existence of a kind of entity.