* FTSEurofirst 300 down 1.6 pct
* Weak Wall Street, commodity prices knock shares
* Rolls-Royce slumps after another profit warning
* Aegon and RWE also fall after results (Adds closing prices)
By Alistair Smout
LONDON, Nov 12 (Reuters) - A top European stock index posted its biggest fall in six weeks on Thursday, as weakness in U.S. equities and commodity prices combined with poor earnings updates to drag shares lower.
The pan-European FTSEurofirst 300 index was down 1.6 percent at 1,470.05 points by the close, posting its biggest daily decline since Sept. 28.
The index weakened with Wall Street after jobs data supported the view that the U.S. Federal Reserve could raise rates in December.
Weaker-than-expected earnings reports in Europe included another profit warning from Rolls-Royce, which sent the British engine maker’s shares skidding 19.6 percent - their biggest one-day percentage drop in 15 years.
Commodity stocks were the biggest fallers by sector, with basic resources firms down 4.2 percent and energy firms down 3.1 percent.
A strong dollar and concerns about oversupply sent copper to a six-year low, while an OPEC report that a market surplus in oil would persist sent the price of Brent lower.
“Combine plentiful supply with a strong-dollar view, and commodity prices will struggle,” said Chris Faulkner MacDonagh, global markets strategist at Standard Life.
“Even if there are pockets of value in the energy or commodities space, they can stay cheap for quite a while, and we have yet to see that positive catalyst.”
Rolls-Royce downgraded its profit forecast for 2016, its fourth profit warning in just over a year. It blamed sharply weaker demand for spares and services to existing aero-engines.
“Yet another profit warning has shocked investors, with a review of its current shareholder payments policy a major negative,” said Keith Bowman, analyst at Hargreaves Lansdown.
“Additional headwinds for selected aerospace and offshore marine markets have been flagged, including sharply lower volumes of corporate jets and ongoing difficulties for its oil-impacted Marine business.”
German utility RWE fell 9.6 percent after warning it would only barely reach its full-year net profit target, while Dutch insurer Aegon missed forecasts with its loss, and dropped 11.1 percent.
The third-quarter earnings season in Europe is drawing to a close. According to Thomson Reuters StarMine data, 84 percent of companies in the STOXX Europe 600 index have announced third-quarter results so far, of which 51 percent have met or beaten analysts’ forecasts. On the revenue front, only 47 percent of companies have met or surpassed expectations.
Shares in BAE Systems rose 3.8 percent after sources told Reuters that it would sell its less profitable operations, boosting the stock despite the defence firm seeing flat earnings for 2015.
Europe bourses in 2015: link.reuters.com/pap87v
Asset performance in 2015: link.reuters.com/gap87v
Today’s European research round-up (Additional reporting by Atul Prakash; Editing by Susan Fenton/Ruth Pitchford)