Is Hegel important for understanding Marx as Lenin said?

I understand basic concepts like negating the negation, and a looser less concrete of sublation in general. I own 3 books by Hegel all 3 in English, including Science of Logic, Phenomenology, and Lectures of the Philosophy of History. They're all pretty dense books but I absorbed a lot of imformation just in the introduction to phenomenology. Bordiga also had a paper on Hegel and ocassionally mentions things in papers that fancy Hegelian phrasing