The U.S. Patent and Trademark Office officially published a series of 56 newly granted patents for Apple Inc. today. In this particular report we cover a fully magnetic Apple Watch Band. While Apple offers leather and Milanese Loop Apple Bands that offer magnetic closures, Apple's granted patent covers a band that is completely magnetic. The watch would be able to be attached to a Mac, a kitchen fridge or fold in way that would act as a protective case when not in use as presented in patent FIG. 5B below.  

Apple's granted patent 10,206,463 has a history going back to 2013. Its latest filing was in Q3 2015. You could review the patent for more details here.

Apple was also granted a second Apple Watch band patent titled "Band Tightness Sensor of a wearable device" under number 10,206,623. 

Apple's invention relates to sensing the tightness of a band attaching a wearable electronic device to a user's body part. A wearable electronic device may have a processing unit and a health sensor included in a housing, a band operable to couple the housing to a body part of a user, and a tightness sensor coupled to the band. The tightness sensor may be operable to produce a signal indicative of a tightness of the band on the user's body part. The processing unit may determine a tightness of the band based on the signal and perform various actions such as evaluating the signal for changes in the tightness of the band according to operational tolerances of the health sensor, providing output directing the user to adjust the band to improve operation of the health sensor, monitoring changes in the tightness of the band and adjusting a measurement obtained by the health sensor, and so on.

Apple has another invention covering this same theme that you could check out here. Apple has also filed for another patent on this theme of keeping the band snug so that health sensors could accurately measure vitals late last month.