Speaking as a former but very active member of the media, I can assure you, however, that the corporate owners exercise very little editorial influence on the media outlets they own. When Rupert Murdoch for instance launched Fox News, he almost certainly hired a rightwing CEO who would provide an alternative to all the other television/cable media outlets that were all leftwing. And he set the standard that all newscasts would be balanced with perspective from all ideological sides. Fox has held to that standard pretty darn well. Editorially, more rightwing than leftwing. But in the newscasts, you'll get both sides (which most leftwingers then conclude is slanted rightwing.

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But Murdoch doesn't tell the news managers what stories to run or what slant to put on them.
The CEO of General Electric, when GE owned NBC and its affiliaites, at one point ordered the managers to say nothing negative about Barack Obama or his administration. Of course that drove NBC far left from where it had been but they obeyed the order. He didn't, however, tell them what stories to run or what slant to put on them.
Now that Comcast has taken over the NBC family, I've seen a decided editorial shift away from the far radical left. And their numbers are coming up as a result even though they still tilt left.
The problem with Fox, CNN, and all the alphabet networks is that they no longer do much of anything really in depth. They give the public 30 second soundbites of this and that and the public has learned to prefer to get information in that way and as a result is a far less well educated public. As polarizing and sometimes despised figure as Glenn Beck is, he was the one exception. He did some deep research and provided competent, in depth perspective on a lot of stuff. But he's leaving. And there will be nobody to do that anywhere except the occasional documentary program that most people no longer take time to watch.