Daniel Halpin (born 1985), also known as Tox, is a British graffiti writer. He has found fame for adding his tag, always simply the word Tox followed by a number indicating the year, in a very large number of locations across the London Underground network and walls around London and Glasgow. He was convicted of criminal damage in June 2011 and imprisoned after a history of ignoring ASBOs. Prosecutor Hugo Lodge told the court: "He is no Banksy. He doesn't have the artistic skills, so he has to get his tag up as much as possible." After his trial Ben Eine, another graffiti artist, criticised his work, saying: "His statement is Tox, Tox, Tox, Tox, over and over again." he said that the tags are "incredibly basic" and lacking "skill, flair or unique style". A sentence of 27 months was later passed, the judge commenting "There is nothing artistic about what you do".
Banksy created a mural in Camden Town, close to Halpin's home, showing a small boy blowing bubbles that formed the Tox tag after his imprisonment. It is not clear whether the image was a sign of support or further criticism of his simplistic style.
Halpin was selling canvases bearing his tag for £75 each in 2009.It's claimed He spent the majority of his canvas earnings feeding his on-going addiction to the synthetic drug Spice. 
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- "Prolific graffiti vandal jailed for 27 months". London Evening Standard. 18 July 2011. Archived from the original on 2011-12-17. Retrieved 2012-02-09.
- "Banksy uses 'tag' of jailed graffiti artist Tox as latest artwork appears on London street". Daily Mail. 24 June 2011. Retrieved 2012-02-09.
- "Vandal cashes in on law loophole". BBC News. 11 September 2009. Retrieved 2012-02-09.