A recently published paper which examines price manipulation of bitcoin has found that it is likely the actions of a single agent drove the price of the cryptocurrency from $150 to $1000 in late 2013.

The paper, which was written by Tyler Moore, Tali Oberman, JT Hamrick and Neil Gandal, investigates what it describes as "suspicious trading activity" which occurred on the now-closed Mt. Gox exchange, and suggest that this activity was linked to the massive gains in value bitcoin experienced in 2013.

On days when the suspicious account was active on the exchange, the USD/BTC exchange rate gained around 4% on average, with the rate declining when the account was not active.

The suspicious account appears to have used two bots to buy and sell bitcoins which the account did not own. Each fraudulent transaction was recorded as part of the Mt. Gox trading volume. These fraudulent trades slowly pushed up the price of bitcoin and encouraged others to get involved in the market. 

The paper goes on to posit that the bots were also used to cover up an attack by hackers which targeted the Mt. Gox exchange, and suggests that in June 2011, when around 650,000 bitcoins were stolen, Mark Karpeles, the owner of the exchange took steps to cover up the loss.