handle Japanese text. NEC did not expect it to become the first successful laptop computer. In Japan, a typical office layout is an open office that is made up of rows of tight desks, so laptop computers received a good reception from corporate customers. In the same month, NEC introduced the PC-98LT laptop computer. This model had poor compatibility with the PC-9801 and could not gain a significant profit. NEC understood, despite difficulties, that the PC-98 needed a new custom chipset to make the motherboard smaller. In March 1987, Epson announced the first PC-98 clone desktop computer and named it the PC-286 series. NEC investigated and sued Epson on the claim that its BIOS infringed their copyright. Epson canceled their PC-286 model 1-4 and released the PC-286 model 0 whose BIOS was made by another team under a clean room design; it did not have a built-in BASIC interpreter. NEC countered that the PC-286 model 0 lacked compatibility with the PC-98. Although it seemed NEC would not be able to win the lawsuit, Epson settled with NEC in November 1987 after considering the damage that would be done to their reputation. The PC-286 model 0 employs an Intel 80286 processor operating at 10 MHz - 25% faster than NEC's PC-9801VX using the same CPU at 8 MHz. In June 1987, NEC released a 10 MHz version of the PC-9801VX (VX01, VX21 and VX41 models). They added a BIOS signature check to their operating systems to prevent non-NEC machines from booting the OSes; it was commonly called an "EPSON check". In September 1987, Epson introduced the PC-286V and the PC-286U and also released the BASIC Support ROM to add a BASIC interpreter to their computers. Epson also bundled the Software Installation Program which was a patch kit to remove the EPSON check. Both machines were received well due to their reasonable prices and better compatibility. In 1988, Epson made annual sales of 200,000 units and successfully established PC-98 clones in the Japanese PC market. In October 1987, Epson released the PC-286L which was a PC-98 compatible laptop before NEC started development of their own laptop. In March 1988, NEC released the PC-9801LV which was a 100% PC-98 compatible laptop. It was accomplished by three custom VLSI chips. These chipsets are also used in other desktops such as the PC-9801UV11 and the PC-9801RA. In July 1989, Toshiba released the J-3100SS branded as