iPhone 4 spam text?

Apple iPhone - iPhone 4 spam text?

call from 949-637-44..
ATT iPhone 4
" Low on Cash?" text message

Is it safe to reply "STOP" to opt out, or will this just confirm my phone# is good and lead to more?

iPhone ATT
Never reply to these spam messages. They do not know if it is a cell phone number or not. Replying just confirms that it is.

I read an article where these spammers are sending out 85 of these messages per minute. AT&T had filed suit against them. I will try and find the article.

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I found the article. It is not AT&T that filed suit, it is FTC. Here is the
link:

http://www.pcworld.com/article/220472/ftc_asks_court_to_shut_down_text_spammer.h\
tml#tk.rss_news