Any member that intentionally posts false information on a trade or deal will automatically receive a warning. Multiple warnings and/or posting of false information will result in a 3 day suspension if not longer. It will depend on how many times an administrator or moderator has had to deal with it.
Many members on the forums browse the threads and keep up with any updates on the trading/free agency front, especially in the offseason and around the trade deadline. Trying to pass off a fake rumor or update as legitimate is frowned upon and will do nothing but rile up the other members.
If you're a new member and unaware of these rules that's fine, but our veteran members should know better. It will not be tolerated.
Just don't post any false information. Making the other members angry won't get you anything but a warning or potentially a suspension. It's not worth it.