EXCLUSIVE: Hedge funder Kyle Bass is at war with big pharma, but he's long this one pharma stock

Hedge fund manager J. Kyle Bass has snapped up a large long position in Irish manufacturer of over-the-counter pharmaceutical company Perrigo, Business Insider has learned.

Perrigo (PRGO) is now Hayman Capital's second largest equity position.

This is significant because Bass has been at war with the US pharmaceutical industry since the beginning of this year.

So far this year he's filed 13 inter partes review (IPR) petitions with the US Patent and Trademark Office challenging the patents of six publicly-traded pharma companies.

It's part of a new "short activist strategy" where Bass writes an IPR challenging the validity of a patent, while also shorting the company's stock. For this, Bass has even set up a separate pharmacy vehicle within his fund. The idea is that this will end "pay for delay" for drugmakers and ultimately lower drug prices.

Bass is scheduled to speak at the SALT Conference in Las Vegas. We'll be covering the event, so be sure to check back for updates.