And everyone else uses batteries because of Wacom patents. At least that was the case 5 years ago.

And Apple, the richest company on earth, can't afford a license, or what?

Wacom may well decide that the competitive advantage to them having better styluses than the ones Apple can make is worth more than any amount of money Apple could offer.

Beyond the issue of whether Wacom wants to license it in the first place, even if they did, it's probably a high per unit cost (Wacom is a premium-pricing sort of company), and it's in the tablet, not the pen. What percentage of purchasers will even want the pen? I'm guessing it'll be pretty low.

Depends on software support. I remember with WinXP tablet edition, it came with 'Windows Journal', which was good enough to take all my classnotes.

Wacom may not be willing to license it.

Oh, is that why? I thought current multi-touch technology interfered with the Wacom-style force sensor, but I could have imagined that.

From what I remember when I had a wacom tablet in the 90s and 2000s, the tech was something like RFID where the active tablet would read the passive puck and stylus and get sub millimeter accuracy from triangulation. This included tilt and angle of the stylus.

The stylus pressure and buttons was a sensor on the stylus that was sensed by the tablet.

The screen or surface didn't have any sensors.

Very informative, thanks!

Nope. Surface Pro 1 (and 2?) used Wacom tech, had 10-point multitouch, and the stylus didn't need batteries or recharging. The induction stuff that Wacom does is pretty cool.

exactly (that's why they are called 'active digitizer')

Induction basically.