Staff at the Robin Hood Tax group, which is campaigning for a 0.05 per cent tax on speculative banking transactions, have accused investment bank Goldman Sachs of spamming their web site.
The Robin Hood Tax, which was officially launched by actor Bill Nighy, has a poll on its web site to gauge the popularity of the proposed tax. Shortly after the poll was set up it received almost 5,000 votes against the tax in just over 20 minutes.
Staff checked their server records and found that the votes came from just two servers, one of which was owned and operated by Goldman Sachs.
"We have just received this information, and we are investigating the matter fully," said Goldman Sachs in a statement.
A spokesman for the Robin Hood Tax campaign told The Guardian that the votes had been removed from the site.
"It's great that public support for a tax on banks' financial transactions is making people in the City of London sit up and notice," he said.
The campaign has been set up to persuade the government to implement a 0.05 per cent tax on all speculative financial dealings,
The levy would raise hundreds of billions in revenue and, it is hoped, dampen future speculative bubbles, such as last year's large increases in the cost of oil.
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