The Brent/WTI spread has historically ranged between $4/bbl and $8/bbl, but it can expand or contract based on factors related to U.S. and international supply and demand conditions. For example, the Brent/WTI spread hit nearly $14/bbl in April 2011 when protests sparked market fears of significant oil supply disruptions in the Middle East.

Oil prices fell more than 3% on Thursday on a Financial Times report that Saudi Arabia, the world's top crude exporter, will give up its $100 price target in preparation for raising output, along with OPEC members and allies in December.

The kingdom is resigning itself to a period a lower prices, sources told the FT. Oil markets spiraled on the news, falling as much as 4% on Thursday. Sign up to get the inside scoop on today’s biggest stories in markets, tech, and business — delivered daily. Read preview