UBS hit by further $4bn write-down By Haig Simonian in Zurich Published: January 30 2008 07:21 | Last updated: January 30 2008 07:21 UBS, one of the biggest casualties of the US subprime crisis, on Wednesday revealed a further $4bn in write downs on its portfolio of troubled mortgage-related securities. The surprise announcement, coming ahead of the Swiss bank’s annual results on February 14, means UBS will report a net group loss of about SFr4.4bn ($4bn) for 2007. UBS said the full-year loss, which it had signalled when disclosing initial fourth-quarter subprime writedowns of $10bn last month, stemmed from additional...