The British government allows large hedge funds to conduct their own exit polling. And while they're not allowed to release their findings until 22:00 British Summer Time (BST), there is no prohibition against their trading based on the data they collect. Properly sampled Brexit exit polling in UK voting is extremely accurate (usually within a +/- 1% error).
Hours Ahead
These funds will have a good indication of the Brexit vote by midday BST and will almost certainly have solid data by 18:00 BST. There is an embargo on publishing results until 22:00 BST. Thus, hedge funds will have a lead of many hours over the average market speculator. The current betting odds put the outcome at 75% “remain”.
My view is that a trader should not attempt to maximize profits on any given government report, event, day, week, month or even year — but aim to construct risk management practices geared to the longevity of market speculation over decades. Accordingly, I have covered all financially related positions.