The appearance of pattern marks, die lines and liner marks has been and continues to be an issue of contention in the realm of forensic tire analysis. These conditions have been recognized for many years and there is no dispute whatsoever that they exist. The differences in opinion center on the question of what these conditions mean in terms of a tire's structural integrity. Do they reflect some anomaly or defect that occurs somewhere in the manufacturing process, or are they a reflection of some design deficiency that occasionally manifests itself after the tire is placed in service? Allegations such as these are sometimes used as the basis for liability claims against the tire manufacturer. On the other hand, could the appearance of these conditions be the result of some abnormal service conditions that contribute to the tire's demise? The research that I will be discussing gives us factual information that we can use as a basis for answering these questions.