The first thing I thought of as a patent attorney was the potential infringement liability. If indeed the turbines at issue are from the 1980s, to the extent they were patented, the patents have expired by now.But if these companies are servicing turbines made more recently, infringement could be an issue. Under U.S. patent law, once a patented article is sold, repair of the article is permissible, but reconstruction (making an essentially new article on the template of the original) constitutes infringement. The line between repair and reconstruction is not always clear and depends on the facts of each case. The types of refurbishment that the U.S. Court of Appeals for the Federal Circuit has held to be permissible repair include re-applying a non-stick coating to a cooking device, replacing an inner container for medical waste, and replacing disks in a tomato harvester head. By contrast, when an entirely new cutting tip was created for a patented drill bit after the existing cutting tip could no longer be sharpened and reused, the Federal Circuit found the overhaul to be reconstruction. Two key issues run through the case law on repair and reconstruction. The first is whether the entire patented article as a whole can be viewed as having completed its useful life. In these cases, refurbishment typically is deemed infringing reconstruction. The second is whether the whole patented article consists of a combination of unpatented parts. In those cases, even where refurbishment is extensive and includes disassembly, modification or replacement of many of the unpatented components, the process is likely to be viewed as permissible repair. So, assuming the possibility of overhauling patented wind turbines, if the used or broken turbines still have useful life in them and consist of unpatented blades, generator, gearbox, etc., these resellers are likely to be in the clear. On the other hand, if the turbines are spent or have anything like the patent protection of Clipper Windpower’s Liberty wind turbine, an overhaul could rise to the level of patent infringement. Another factor, of course, is authorization from the patent holder. Halus’s website says the company specializes in remanufacturing wind turbines originally produced by Vestas, but it’s unclear whether there is some type of partnering arrangement between the two companies. Eric Lane is a patent attorney and intellectual property lawyer at Luce, Forward, Hamilton & Scripps in San Diego, where he is in the Intellectual Property and Climate Change & Clean Technology practices. Eric is the founder and author of Green Patent Blog, which provides discussion and analysis of intellectual property law issues in clean technology.