WHAT would the country’s “most notorious patent troll” advise a guy under attack from a patent troll? Or, put more judiciously, a company that bears the outward appearance of a patent troll?

I posed this question to the man with the notoriety, Erich Spangenberg, who runs IPNav, asking if he had any words of advice for a Chicago entrepreneur named Peter Braxton. Mr. Braxton, a former Air Force pilot, was in desperate shape when we first spoke about a month ago — so desperate that he was borrowing money from his mother and brother for living expenses. To understand how he got there, and to set up what turned out to be a rather surprising conversation with Mr. Spangenberg, let’s rewind Mr. Braxton’s story.

Three years ago, Mr. Braxton was stuck with about 200 people, waiting to get into a nightclub at the Encore Hotel in Las Vegas. A few days later, he conceived an app called Jump Rope. It would give users the opportunity to pay some fee to get to the front of a line — at a club, a restaurant, a museum or any place where a premium for entry could be charged.

Mr. Braxton, who at the time worked at Credit Suisse in Chicago, raised about $250,000 from friends and family to make his idea come to life, with more promised as the company grew. He hired code writers and two employees.