Editing 86-DOS (section)

===Creation of PC&nbsp;DOS===
Microsoft purchased a non-exclusive license for 86-DOS from Seattle Computer Products<ref name="86-DOS_License"/> in December 1980 for {{currency|amount=25000|code=USD|linked=no}}.{{Citation needed|date=April 2013}}<!-- Lots of third-party sources state 1980-12 and US$25,000, however, the license agreement was signed on 1981-01-06 and the total payments described in there depended on some conditions. This needs to be sorted out in better detail. --> In May 1981, it hired Tim Paterson to port the system to the IBM&nbsp;PC,<ref name="Hunter_1983_Roots_of_DOS"/> which used the slower and less expensive [[Intel 8088]] processor and had its own specific family of peripherals. IBM watched the developments daily,<ref name="Hunter_1983_Roots_of_DOS"/> submitting over 300 [[change request]]s before it accepted the product and wrote the user manual for it.

In July 1981, a month before the PC's release, Microsoft purchased all rights to 86-DOS from SCP for {{currency|amount=50000|code=USD|linked=no}}.<ref name="Hunter_1983_Roots_of_DOS"/><ref name="86-DOS_Sale"/><ref name="Duncan_1988_MS-DOS_Encyclopedia"/> It met IBM's main criteria: it looked like CP/M,<ref name="Beley_1986_MS-DOS_Encyclopedia"/> and it was easy to adapt existing 8-bit CP/M programs to run under it, notably thanks to the [[TRANS (command)|TRANS]] command which would translate source files from 8080 to 8086 machine instructions. Microsoft licensed 86-DOS to IBM, and it became PC&nbsp;DOS&nbsp;1.0. This license also permitted Microsoft to sell DOS to other companies, which it did. The deal was spectacularly successful, and SCP later claimed in court that Microsoft had concealed its relationship with IBM in order to purchase the operating system cheaply. SCP ultimately received a {{currency|amount=1|code=USD|linked=no}}&nbsp;million settlement payment.