In the EU any publication, which is broadly defined, prior to the filing date makes it impossible to obtain a patent, period. This is why RSA was never patented anywhere in the EU. There can be no doubt about the inventive steps and non-obviousness of RSA.
I believe the only thing the US allows is for those filing to exclude material they published themselves. If anyone else substantially discloses their invention prior to the filing date then that is prior art (and grounds for the patent application to be refused).
A fortune article prior to the filing date is probably sufficient unless Microsoft can somehow proved they published that. I suspect this is impossible even in Microsoft's universe.