risk Arbitrage trades are necessarily synthetic, leveraged trades, as they involve a short position. If the assets used are not identical (so a price divergence makes the trade temporarily lose money), or the margin treatment is not identical, and the trader is accordingly required to post margin (faces a margin call), the trader may run out of capital (if they run out of cash and cannot borrow more) and be forced to sell these assets at a loss even though the trades may be expected to ultimately make money. In effect, arbitrage traders synthesise a put option on their ability to finance themselves. Prices may diverge during a financial crisis, often termed a "flight to quality"; these are precisely the times when it is hardest for leveraged investors to raise capital (due to overall capital constraints), and thus they will lack capital precisely when they need it most. Gray market Grey market arbitrage is the sale of goods purchased through informal channels to earn the difference in price. Excessive gray market arbitrage will lead to arbitrage behaviors in formal channels, which will reduce returns due to factors such as price confusion, and may even cause prices to plummet in severe cases. Types Spatial arbitrage Also known as geographical arbitrage, this is the simplest form of arbitrage. In spatial arbitrage, an arbitrageur looks for price differences between geographically separate markets. For example, there may be a bond dealer in Virginia offering a bond at 100-12/23 and a dealer in Washington bidding 100-15/23 for the same bond. For whatever reason, the two dealers have not spotted the difference in the prices, but the arbitrageur does. The arbitrageur immediately buys the bond from the Virginia dealer and sells it to the Washington dealer. Latency arbitrage For very short amounts of time, the prices of two assets that are either fungible or related by a strict pricing relationship may temporarily go out of sync as the market makers are slow to update the prices. This momentary mispricing creates the opportunity for an arbitrageur to capture the difference between the two prices. For example, the price of calls and puts on an underlying should be related by put-call parity. If these prices are misquoted relative to the put-call parity relationship, it provides an arbitrageur the opportunity to profit from the mispricing. Latency arbitrage is often mentioned especially in an electronic trading environment, where the use