The litigated data is presented to contrast the other patent movement. It is useful to see that the scale of litigation (and invalidation due to litigation) is quite small compared to entities simply choosing not to pay fees.
With respect to litigation of patents in a portfolio, the percentage of litigated documents monotonically rises from near zero at year 0 to almost 2% by the end of patent life. Narrow product portfolios vary widely from this benchmark. The “Patent Litigation Frequency” figure shows that rather than having an expected technology “adoption lag” early in the aggregate patent life, there’s an immediate uptick in litigation (about 1%) and a plateau between years 5 and 9. One might expect that there would be a delay in acceptance for something truly new, hence the hockey-stick-shaped graph. In business schools, it is taught that it takes about seven years for something new to be adopted. The same amount of time it takes to go from first funding to IPO — and market saturation for most revolutionary products. If the average of three years prosecution time for a patent to issue is taken into account, the dotted green line drawn over the graph shows this expected seven-year behavior (three years prosecution plus four years delay). Further analysis of the litigated patents shows that almost 80% of these early-litigated patents are continuations or reissues of previously filed inventions.