Ambac Financial has posted a second quarter 2012 net loss of $811.1m, or $2.68 per share, against $102.4m, or a net loss of $0.34 per share during the same period earlier year.

According to the company, second quarter 2012 results were mainly driven by a net loss relating to the extinguishment of Ambac Assurance surplus notes, and higher derivative product losses, partially offset by higher net realized investment gains.

Net premiums earned for the current quarter period were $103m, with an increase of 4%, compared to $99.3m gained during the corresponding period last fiscal.

For the combined financial guarantee, financial services, and corporate investment portfolios, net investment income was $93.8m, down by 2% from $95.6m during the second three months of 2011.

Net realized investment gains for the second quarter of 2012 were $67.1m, an increase of $69.6m over net realized investment losses of $2.5m during the second quarter of 2011.

During the second quarter of 2012, the realized investment gains were largely the result of portfolio repositioning and relative value trades executed in response to market conditions.

Other income for the three months ended on 30 June 2012 was $36.1m, as compared to $9.2m for the same quarter period last fiscal.