Research on intellectual property has focused on formal legally recorded rights that we call deeded, most often measured by granted patents. Meanwhile, other "defacto" IP (mainly purposive secrecy and natural excludability) has become more important because of the increasing closeness of...

This paper identifies three major periods: 1900-1929, 1929-1965, and 1965-1978. In contrast to the middle period, the extreme periods are characterized by rapid growth in private employment and hours worked; because growth in private productivity increases by less, measured labor productivity...