After talking with several specifiers I have started to note companies acquired by others before the purchased website changes. This is intended to help you identify competitive suppliers.
Let know as you learn of others I have not noted. Here is the updated page for 2019:
I am mystified when some websites disappear, but even more baffled when other websites live on as zombies. A case in point is www.ceilingsplus.com. Except for a screen informing us that the company was purchased by USG, the website has not changed since I was separated from the company about 6 years ago. It was out of date then, and is even more so now. Case in point is that it still has a page explaining how its products apply to LEED - 2004. It was a good company then, with GREAT products, but please verify any info on their website before using it.