One assumes so. Although, it's impossible to say for sure. There can be situations with buyouts or whatever where several different people have rights to a slice of what was once a whole pie.
However, practically, it seems to me that Chamber's patents would be a moot point now. I'm not a lawyer, but it seems to me that the patent term would be over for anything Chambers designed. If they were bought out in 1984, it's been more than 20 years, and according to Wikipedia, the patent term in the US is 20 years.