Attempts to resolve the Unix schism between the Open Software Foundation and AT&T with the newly founded Unix International Inc have finally come to an official halt. Although it has been known for some weeks that talks had been making little progress due to the disagreement over the two kernels, the official line remained that negotiations were continuing. At the end of November, however, president Henry Crouse sent a letter to all Foundation members setting out its position. The central obstacle to AT&T’s joining OSF is its insistence that the OSF board of directors mandate System V Release 4 in its entirety as OSF/1, rather than permitting users to select the best available technologies through the open system process, said the letter, which went on: I have reached the conclusion that further discussions with AT&T would be non-productive, and have decided to suspend them. Crouse then assured members that we have no intention of allowing these, or any other activities, to impact our commitment… to deliver a complete open software platform by the end of 1989. The letter, which reached Software Foundation members the same day as the rival Unix International Inc was announced, also revealed the Foundation’s extensive re evaluation of our original decision to use AIX-3 as the basis for our core operating system. The conclusion was that AIX-3 is a technically superior base for OSF/1, and that the licensing terms would provide equitable and stable licensing terms by granting OSF the right to provide source and redistribution rights directly for all or any portion of the code. It also places a ceiling on licence revenues. AT&T spokesman John Scalco said AT&T had been surprised by the letter.