My understanding is that x86 originated from Intel and x86-64 was an extension of it by AMD who had been licensing x86. They agreed to trade so neither paid to license one from the other. So Intel got to use x86-64 because they let AMD have free use of x86. As a result they both keep anyone else from using x86. And of course now a days x86-64 is the only one that really matters. Presumably another company getting involved like Qualcomm would mess up that old deal.
My understanding is that x86 originated from Intel and x86-64 was an extension of it by AMD who had been licensing x86. They agreed to trade so neither paid to license one from the other. So Intel got to use x86-64 because they let AMD have free use of x86. As a result they both keep anyone else from using x86. And of course now a days x86-64 is the only one that really matters. Presumably another company getting involved like Qualcomm would mess up that old deal.