(Bloomberg) -- Investors in oil ETFs have been piling into the asset class -- just as money managers flee the futures market.

Thirteen long-only oil funds posted inflows of just over $500 million last week, the biggest such addition since May 2020. By far the biggest beneficiary was the $2.5 billion U.S. Oil Fund, the market’s largest exchange traded product, which gained about $236 million. 

The flows ran contrary to speculators investing in oil, who continued to cut exposure last week, pulling the biggest position out of Brent and West Texas Intermediate since July. Prices last week plunged to a three-month low on concerns around the impact of Omicron variant of Covid-19 on global growth, having already lost $10 in a single day on Nov. 26. 

Oil ETFs are often seen as a way for retail traders to invest in the market. There are other signs that smaller traders have been active in recent days too:

• Non-reportable long positions in WTI -- those that don’t fit the main reporting categories of swap dealer, producer, consumer or speculator -- jumped by the most since 2017
• CME’s micro WTI contract -- a retail focused product -- posted average daily volumes of 129,000 contracts last week, the highest weekly average since it began trading earlier this year

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