Mariner Bridge is writing down the book value of its US securitisations to $36 million, or 26 per cent below their face value, following exposure to the sub-prime market.
The investments are poorly performing US securitisations in structures with an average 40 per cent exposure to the sub-prime home loan market.
In a statement to the Australian Securities Exchange, the group said write down was by significant provisions and by acquiring some investments at a discount to face value.
"Very strong income in the majority of the company's investment portfolio has offset this lower than anticipated performance in the US Securitisation investments," the statement said.
Mariner Bridge Investments had $302 million of investments at July 19, funded by the company's shareholders' funds of $261 million and the remainder by debt.
Mariner Bridge will be reporting its annual results on Thursday 9th August 2007.