"Equal protection" a no-go for HP at BPAI

The blog 12:01Tuesday has a great post on an equal protection argument made by (former) Coalition for Patent Fairness member Hewlett-Packard, with the post titled BPAI to HP: Equal Protection Clause doesn't save claims from 101 and the punchline:

Appellant [HP] alleges that the USPTO has issued patents to others that contain “propagated signal claims.” Appellant contends that the § 101 rejection of the instant claims is a violation of Appellant’s rights under the equal protection clause of the Fourteenth Amendment to the U.S. Constitution. App. Br. 14.

However, Appellant has not cited any authority in support of the novel legal argument.