LONDON, July 16 (Reuters) - Northwest European gasoline refining margins edged down 57 cents to $43.12 a barrel on Thursday, but hovered near four-year highs on signals of tighter supplies.

• A total of 4,000 metric tons of Eurobob E5 gasoline barges traded on Argus, with BP selling to Gunvor.

• A further 6,000 tons of Eurobob E10 barges traded, sold by Phillips 66, Shell and Petroineos to Varo and BP.

• Product stocks held independently in the Amsterdam-Rotterdam-Antwerp refining and storage hub fell 4.5% in the week to Thursday, data from Dutch consultancy Insights Global showed.

• Gasoline stocks fell 9.3% to 820,000 tons, their lowest since October 2021 on strong exports to Brazil, Canada and the U.S. in addition to fewer imports.

• The U.S. summer driving season has kicked off, van Wageningen added, which was leading to the higher exports with the Strait of Hormuz being effectively shut again. U.S. Gulf Coast gasoline stocks fell to their lowest since 2017 in the week ending July 10.