which specialised is developing and manufacturing test and burn-in sockets, especially zero insertion force (ZIF) sockets, which are used to test semiconductor ‘chips’ and sometimes burn-in programming, without soldering the chip onto a board. Many are loaded by robots, and for certain types of connectors, particularly ball gate arrays (BGA) it is essential that a good connection be established without enough force to damage the solder that forms each ball intended to make the subsequent final connection in a device.
In 1980 Pfaff was approached to develop a ZIF socket by Texas Instruments and apparently sketched the design on the spot on the back of a napkin; such was Pfaff’s reputation that this was enough for TI and later in 1981, TI confirmed they would order and use Pfaff’s socket, though no actual socket was made until July 1981. Pfaff applied for a patent in April 1982 – more than a year after showing the napkin sketch to TI and ultimately obtained three patents, with which he sued Wells Corporation when it copied his ZIF design. However, Wells challenged the patents on the basis of a breach of the on-sale-bar and the Supreme Court concluded that, as the napkin sketch as enough to induce TI to buy Pfaff’s socket, it was indeed an offer for sale outside the 1-year grace period offered by US patent law.
1980, Wayne K. Pfaff developed a new type of computer chip socket for Texas Instruments (TI). In early April 1981, TI confirmed they would order and use Pfaff’s socket. No actual socket was made until July 1981. Pfaff applied for a patent in April 1982.
The Pfaff case is seen as a cautionary tale of failing to apply for a patent on time – however, it should be noted that the case factually turned on Pfaff’s personal reputation, which was such that even a design hastily sketched on a napkin was enough to persuade his customer that what he promised to make would work.