  Let $b(z) = \prod_{n=1}^\infty \frac{-\bar{\alpha}_n}{|\alpha_n|} \frac{z -
\alpha_n}{1 - \bar{\alpha}_n z}$, where $\sum_{n=1}^\infty (1 - |\alpha_n|)
<\infty$, be the Blaschke product with zeros at $\alpha_n \in \mathbb{D}
\setminus \{0\}$. Then $\cls = \vee_{n=1}^\infty \big(z^n H^2(\mathbb{D})\big)
\otimes \big(\prod_{k=n}^\infty \frac{-\bar{\alpha}_n}{|\alpha_n|} \frac{z -
\alpha_n}{1 - \bar{\alpha}_n z} H^2(\mathbb{D})\big)$ is a joint $(M_{z_1},
M_{z_2})$ invariant subspace of the Hardy space $H^2(\mathbb{D}^2) \cong
H^2(\mathbb{D}) \otimes H^2(\mathbb{D})$. This class of subspaces was
originally introduced by Rudin in the context of infinite cardinality of
generating sets of shift invariant subspaces of $H^2(\mathbb{D}^2)$.
  \noindent In this paper we prove that for a Rudin invariant subspace $\cls$
of $H^2(\mathbb{D}^2)$, the cross commutator $[(P_{\cls} M_{z_1}|_{\cls})^*,
M_{z_2}|_{\cls}] = (P_{\cls} M_{z_1} |_{\cls})^* (M_{z_2}|_{\cls}) -
(M_{z_2}|_{\cls}) (P_{\cls} M_{z_1}|_{\cls})^*$ is not compact. Consequently,
Rudin's invariant subspaces are both infinitely generated and not essentially
doubly commuting.
