Patent litigation costs companies millions of dollars in time and lawyer fees, but just how effective are the “patent wars” anyway? Florian Mueller, the founder of the FOSS Patents blog, analyzed 222 smartphone patent assertions — with Android being a major target of many of them — only to find that 90% of those cases have gone absolutely nowhere.

According to Mueller's data, which was charted for us by BI Intelligence, about half (49%) of the assertions have failed thus far, while 42% of assertions were dropped without a comprehensive settlement or a “comparably negative fate.” As it turns out, only 20 or the 222 patent assertions (9%) were able to establish liability, but even in that small sample, only 10 of those 20 cases resulted in “lasting injunctive relief.” Mueller says that number would be even smaller if “the patents underlying Nokia’s German injunctions against HTC had come to judgment in the Federal Patent Court.”

In other words, based on patent cases brought to court by Apple, Samsung, Microsoft, Nokia, Motorola, and a host of others, litigation is, more often than not, a serious waste of time and money for all parties involved.