The US patent courts have been kind to online retailer Amazon over the years, but the company might have a rougher ride as a defendant against IBM.

IBM cracked after four years of trying to get Amazon to buy a licence for patents related to web-selling and advertising, suing for patent infringement in the Eastern District of Texas last week.

The Amazon legal team must have groaned when it saw IBM’s choice of court. The Eastern District’s judges and juries are known for having a soft spot for plaintiffs.

In Texas you defend your property with a gun, and the good burghers of the Eastern District extend that attitude to IP.

Amazon is likely to instruct Kirkland & Ellis. Last year partner David Callahan won a case in Virginia for Amazon against IPXL for infringing its iconic 1-Click online purchase system.

You never know, Callahan might be able to catch up with some colleagues down south. Fellow Kirkland litigator Linda LeBruin will be in town defending BlackBerry maker Research In Motion from a patent attack from Visto.