why take such stupid risks all the time?, page-10

A cfd (contract for difference) is a derivative (a synthetic financial instrument derived from an actual financial instrument - shares).

One can go long (buy first and sell later) or short (sell first and buy later).

When you short 10,000 TLS, you buy a cfd from the cfd provider and the cfd provider sell 10,000 TLS shares in the market at the same time, to give you the open position.

If you close the cfd position in say 10 days (or whenever, no expiry date is an advantage), your cfd provider will buy TLS shares in the market to close the position. Profit or loss goes to you.

In TLS's case, when it became obvious to hedge funds that the share price would fall, due to profit downgrade and new CEO using the broom, strong short selling drove downward price momentum.

When these positions close, if roughly at the same time, they lead to buying, which can drive the price up a bit.