Julie, As both an editor and a press release sender, you don't have to worry about copyright. In fact, press release writers would prefer if you don't say that your material comes from a press release because then it has more credibility. For a writer or editor, there are basically three ways to use a press release. Second way is to call the contact to get more information and write a story that way.
Third way is to lift part of the material from the release.
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