IP in the economy: how many jobs does it support?

The United States Patent and Trademark Office recently issued a report, Intellectual Property and the U.S. Economy: Industries in Focus, by Peggy Garvin. According to the press release which accompanied its launch, the report:
"... finds that intellectual property (IP)-intensive industries support at least 40 million jobs and contribute more than $5 trillion dollars to, or 34.8 percent of, U.S. gross domestic product (GDP). 
While IP is used in virtually every segment of the U.S. economy, the report identifies the 75 industries that use patent, copyright, or trademark protections most extensively. These “IP-intensive industries” are the source – directly or indirectly – of 40 million jobs. That’s more than a quarter of all the jobs in this country. Some of the most IP-intensive industries include: Computer and peripheral equipment, audio and video equipment manufacturing, newspaper and book publishers, Pharmaceutical and medicines, Semiconductor and other electronic components, and the Medical equipment space".
I always have some reservations about exercises, since the are always going to be problems in measurement.  In the first place, if IP is construed in wide enough terms, there's scarcely a business of any size that isn't supported by it. Lists of customers and suppliers, licensed software, business and trading names are pretty well ubiquitous. There's also the question of causation: how many of the jobs in question are specifically related to the existence of IP, how many to the provision of a service or the supply of goods that would have generated employment even if it had been generic and devoid of IP protection?

You can access the full (62-page) report here.

Thanks are due to Chris Torrero for the link.
Automotive Technology Review, Automotive Technology Review,