Whether it will ever be announced or released remains to be seen, but references to the Surface Mini in the Surface Pro 3 manual confirm that the device does exist.
In what could only be seen as an awfully careless slip-up, Microsoft has confirmed the existence of the Surface Mini by leaving references to the tablet in the user manual for the Surface Pro 3.
The manual, which is available from Microsoft’s website, mentions the Surface Mini several times, taking the reader through the process of unlocking the device to take a quick note, pairing it with the Surface Pen and waking up the Surface Mini by pressing the button on the pen, and so on. The Surface Pro 3 was similarly leaked by Microsoft itself a week ahead of its announcement, and it looks like the company hasn’t managed to be any more careful since then.
The Surface Mini was expected to be revealed alongside the Surface Pro 3, but rumors indicated that Microsoft CEO Satya Nadella pulled the device at the last moment. Reportedly, the Surface Mini has only been delayed and not canceled, which might explain why Microsoft didn’t go ahead and delete those references. There’s still no telling if the Surface Mini will eventually be released, but one thing is certain: it does exist, whether Microsoft is willing to show it to the world or not.