The 45,000-contract swing was the biggest since March 2020 and sixth largest since euro futures contracts were launched in the 1980s.
chartSimilarly, funds reduced their net short sterling position by 13,000 contracts, the biggest move in six weeks.
In rates, CFTC speculators cut their net short position in three-month "SOFR" futures by 33,000 contracts to 788,000 contracts, the smallest net short in seven weeks.
They reduced their net short position in 10-year Treasuries futures by 123,000 contracts, the biggest short-covering move in almost five months.
And in equities, they scaled back their net short position in S&P 500 futures by 61,500 contracts to 219,500, the smallest net short in two months.