Using other peoples copy, content, words, whatever you want to call it, as source is legal, but questionably so, and the law there is that it cannot be (I don’t speak legal, and I’m not going to spend an hour looking up the quote) harmful, or take away from the original source, and the original source must be credited, which in this case, I don’t believe it was.
But what that breaks down to is it is generally ok to use a snippet of an article, and quote it as a source… so long as you give credit to the original author.
A snippet, not a press release in its entirety, with the benefits changed from them you to you. The idea behind a press release isn’t really even for it to be reposted, that’s kind of an online thing, in the offline world press releases are sent out to relay facts, so that articles can be written.
However, K-Mart would not be able to use the work of Wal-Mart’s marketing team, and use their entire press release, just changing the name of the store, nor would they remain reputable if they did.
In any case, back to that original law, if the original author, or owner of the content states that they have been stolen from, obviously they believe that their content has been diluted, and you can be held liable for that theft.
Simplest solution… take down the offending stolen content, most people are happy with that… if that solution is not enough, and a company that claims to be ‘serious’ and ‘professional’ boasting about their several staff members, can not agree to remove the content from a blog, and hire someone to write their own copy, there are other a few other remedies…
1. You report the stolen text to google (getting rid of any possibility of adsense accounts on the domains that steal content)
2. You report the domains that are using your content in effort to get them banned from the search engines.
3. Report them to their host, point them to both copies of the content, and attach proof of ownership.
4. Legal Recourse can be taken, monetary damages can be sought after, this is pretty rare though, because it’s very involved, especially if both parties aren’t even in the same country. This is the reason most people use the Google DMCA road.