Humans, as well as other species, have always relied on imitation to survive in a hostile environment, make tools, and outdo rivals and protagonists. They have learned not to reinvent the wheel — even before there was one. As communication and transportation have advanced, opportunities for imitation have burgeoned: globalization and technological advances have expanded the ranks of imitators and have made imitation more feasible, more cost effective, and much faster.
It took one hundred years for nineteenth-century innovations to be exploited by less-developed nations, but inventions made in the second half of the twentieth century were copied, on average, within two.
The average time to widespread imitation declined from 23.1 years between 1877 and 1930, to 9.6 years for products introduced between 1930 and 1939, and 4.9 years for those introduced after 1940; the time before imitator entry declined by 2.93 percent.
An imitation lag that was twenty years in 1961 was down to four years in 1981, and down to twelve to eighteen months by 1985.
The accelerated pace of imitation is evident for almost any product. Imitations of the phonograph showed up in thirty years, whereas compact disc players were imitated in three. It took a decade before the first imitation of the Chrysler minivan appeared; QQ, a Chinese copy of GM's minicar, showed up within a year. In 1982 generics constituted a mere 2 percent of the U.S. prescription drug market, but by 2007 they made up 63 percent. In the early 1990s Cardizem lost 80 percent of the market to generic substitutes within five years of patent expiration; a decade later, Cardura lost a similar share in nine months; and Prozac, an Eli Lilly blockbuster drug, lost the same market share in only two months.