Robocall received a few times.  I finally decided to learn more so opted in to sign up for the duct cleaning.  When I reached a live person, I mentioned I needed to learn more about the company.  The representative immediately hung up on me.

They called themselves Green Clean and said they have been in Normandy Park near Seattle for 5 years.
You'll all know more about them when you see the explosion on the news.

These people have left so many messages on my home phone about duct/dryer vent cleaning.  They always call in the middle of the day so I'm not home to answer, and the number they use to call isn't the call back number (and they never state their name in the message) so no way to track them down and tell them to remove me from the call list.  Very annoying!  If I ever am home when they call, I'm inclined to give them an earful, but it sounds like they will just hang up.