The idea behind is to start with the companies you (I) know about and make a finite list. For Every company You can start a new thread - and later, on Monthly basis, I'll put in a comprehensive list as a sticky, for all the companies we add in for that month. Please feel free to add in any company that you want to add in to the list, however make sure -- it works for/on Mainframes.
This section lists all the companies which do business in or with Mainframes - in other words, for example - The Bank "A" does have a Mainframe System to run its "Financial Institution" but it does not create (Technical)Products for Mainframe. On the other hand, "Company B", has its line of Business and Products specifically developed for zOS, MVS, or Mainframes platforms -- this section list both kind of companies. However in doing that one can not abuse any company in any way - if your post is found doing so, it will be deleted from the Forum without any intimation and worse you mihgt be banned from this Forum!
There is a separate thread "Relative Questions on Companies." which can list all the discussion which is not about "Company's Profile" and of general nature about this section of the Forum.
Good Luck!
Note : This website and The Staff of this Website is not a spoke-person of any of these companies. This is a "personal collection" of the information about the companies and have no direct relation with them, unless specified.