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By Douwe Miedema
WASHINGTON, April 8 (Reuters) - The top U.S. derivativesregulator is probing a widely used benchmark for swaps, thetrade body overseeing the rate said, dealing a further blow tothe market after the sprawling Libor probe.
The Commodity Futures Trading Commission (CFTC) hassubpoenaed the International Swaps and Derivatives Association(ISDA) over its ISDAfix benchmark, widely used toanchor market rates, a spokeswoman for ISDA said.
Bloomberg reported on Monday that the CFTC was investigatingderivatives broker ICAP Plc and as many as 15 banks in a probe into the possible manipulation of the benchmark.
The CFTC, which oversees the $640 trillion derivativesmarket, wants to know if ICAP's staff were colluding with thebanks, who stand to profit from inaccurate quotes, Bloombergsaid, quoting people familiar with the matter.
ICAP said in a statement it had no knowledge of theallegations prior to the Bloomberg report. The broker iscooperating with the CFTC's wider probe into the area, it said.
The CFTC did not immediately return a request for comment.
The CFTC's probe came about as it was working with Europeanregulators in the scandal surrounding the Libor interbank ratebenchmark, Bloomberg said, which has lead to have fines for UBSAG, Royal Bank of Scotland Group Plc andBarclays Plc.
The fixings are based on a survey of panel banks for thedifferent currencies, according to the ISDA website. ICAPcollects these contributions and sends them on to ThomsonReuters Corp, which calculates the fixing.
A spokeswoman for Thomson Reuters had no immediate comment.
