How much did Borussia Dortmund bus 'bomber' stand to gain?

There surely have to be easier ways of making a few quid than trying to blow up other people.

The saga of 'Sergej W', the German-Russian arrested for the bombing of the Borussia Dortmund (Swiss: BVB.SW - news) team bus , is one of the more bizarre episodes in the history of financial derivatives.

The suspect is alleged to have used an instrument known as a 'put option'.

These products convey the right, but not the obligation, to sell an asset at a fixed price at some point in the future.

They are commonly used by investment professionals to bet on the price of an asset, such as a stock or a bond, falling.

For example, shares of ABC (KOSDAQ: FED642.KQ - news) plc are currently trading at 500p.

Fred, an investor, thinks that the shares are over-valued and suspects they might fall.

So he buys a put option entitling him to sell 10,000 shares in ABC plc at 500p each.

A few days later, ABC plc issues a profits warning, sending the shares down to 300p. Fred's option is said to be 'in the money', in the jargon, and so he exercises the option.

He has made a profit of £20,000 (10,000 x 500p-300p), before taking into account his dealing costs.

The opposite of a 'put' option is a 'call' option, in which the buyer receives the right, but not the obligation, to buy an asset at a set price in the future.

But trading in options is a risky business.

Quite often, the underlying asset will not reach the price that it needs for the buyer of the option to make a profit on it - in such circumstances, the option is said to be 'out of the money'.

And betting on the likelihood of a share price falling is particularly risky.

If you own a share and its price falls, your downside is limited - the maximum amount you can lose is the sum you that invested.

If you bet on a share price falling, but instead it rises, then in theory the amount you can lose is infinite.

Simon Cawkwell, the professional stock market trader known to his followers as 'Evil Knievil', has spent a lifetime betting on share prices falling.

He has made a good living from it, thanks to his ability to analyse company balance sheets forensically, but there have been occasions where a stock he has bet on to fall has instead risen - and he has, on occasions, lost as much as £250,000 in the process.

Apart from his alleged violent intentions, one of the most startling things about 'Sergej W' is the relatively small profit his scheme will have generated.

He is said to have bought a put option giving him the right to sell 15,000 shares in Borussia Dortmund, although it is not known what price the option entitled him to sell.

However, with Dortmund shares trading at €5.61 each on 11 April - the day the attack took place - and having closed last night at €5.36, his putative profit will have been no more than €3,750.

As pathetic is that he bought the options using a consumer loan.

There were rumours, in the aftermath of the 9/11 terror attacks, that members of Al-Qaeda had used options contracts to speculate on falls in airline stocks.

These were taken so seriously by financial regulators that they actually launched an investigation - only to conclude no such trades had taken place.

'Sergej W', in his own warped way, genuinely does seem to be something of a financial pioneer.