It's not possible to remove a message embedded within the Bitcoin Blockchain. Locked Post assigns a sequential number to the beginning of every embedded message ("L1,Message" - sequence number "1" for example) - this acts as a easy way to verify that the data has not been modified or removed (by allowing anyone to check the sequence hasn't broken and that the web-site content matches what is stored in the Blockchain [The web-site provides links to various services that allow you to view Bitcoin transactions and therefore the embedded data within.]). You can see every message ever posted here: https://bitaps.com/1K69sEhUwNgiva3xzPnToxS89dzydU7nPm I will also eventually release code to easily verify the web-site.

http://pastebin.com/Ng7AFm3T/ - https://lockedpost.com/validate/PHP-Validation-Code/