Royal Bank of Scotland has lost in the latest round of a potentially expensive court battle against a US financial firm, with a judge in London ruling that it acted fraudulently.
The case concerns the handling of an asset at the height of the credit crunch more than four years ago.
A London appeal court overturned a previous ruling in the Edinburgh-based bank's favour, in which it had been awarded £19m.
This was despite court evidence from an RBS trader, Sam Griffiths, being found to be unreliable.
This was "concealing and mis-stating facts", it has been ruled by the Court of Appeal, which said he was acting on behalf of his employer.
Described as a "distressed credit trader" in RBS's special situations group, Mr Griffiths was aged 27 at the time of the financial crash, and has since been sacked by the largely state-owned bank.
The other part of Friday's ruling is that Highland Capital Management, based in Texas, is now allowed to take the case to a Texan court.
That is where it is pursuing Royal Bank of Scotland for $100m (£67m), including damages. RBS had sought to get the appeal court in London to block the right to move to the American jurisdiction.
A ruling by Lord Justice Aikens said the previous judgement in Royal Bank's favour "was obtained by the fraud of RBS through the mis-statement and concealment of facts by Sam Griffiths".
An RBS spokeswoman said the bank was not commenting.
A Highland Capital Management spokesman said: "We continue to work diligently to protect the rights of our investors.
"This judgment validates Highland's position that no financial institution, regardless of size, is above the law.
"We look forward to pursuing Highland's case against RBS in Texas."