Most employees sign away their rights to anything they create when they sign an employment contract. Whether Dr. T did is unknown. The wiki article I provided does address some aspects of ownership:

There are many ways in which an inventor might be compensated for a patent. An inventor might bring the patented product to market under the protection of the monopoly created by the patent. The inventor may license a patent to another entity for an up front fee, an ongoing royalty or other consideration. The inventor may also sell the patent outright. Henry Woodward, for example, sold his original US patent on the light bulb to Thomas Edison who then developed it into a commercially successful product.

I was quickly able to find these cases, the first one interesting for recent events......

http://webcache.googleusercontent.com/search?q=cache:P8Ttr5u5Ek0J:2012thebigpicture.wordpress.com/2014/03/23/rothschild-inherits-a-semiconductor-patent-for-freescale-semiconductors/+&cd=9&hl=en&ct=clnk&gl=ca

This one says that state law directs who owns what after death...

http://dunlapcodding.com/phosita/2004/10/patent-rights-after-death