Are there any particular risks that one should be aware of when using SSFs to either invest excess funds or borrow funds at available synthetic rates?


While the High and Low Synthetic strategies are both hedged positions, the futures leg is subject to a daily cash variation of the mark-to-market gain or loss whereas the stock leg is not (mark-to-market gain or loss is reflected in account equity but there is no cash impact until the position is closed).  If, for example, an account holds a High Synthetic position and the stock prices increases significantly, the resultant variation pay on the short futures leg may erode the account’s cash balance resulting in a debit balance which is subject to interest payments.  The net effect in this example would be to reduce and potentially erase the earnings on the High Synthetic position