Bitcoin (BTC) risks a spate of “profit taking” and price weakness, even as institutional buying surges.

In his latest analysis on X on July 23, popular trader Skew warned of a “headline curse” as the United States spot Bitcoin exchange-traded funds (ETFs) took in over $500 million.

ETF flows not enough to sustain BTC price upside

Bitcoin ETF popularity is enjoying a renaissance this week, but the good times are far from guaranteed to stay, Skew says.

After the largest US spot ETF, the BlackRock iShares Bitcoin Trust (IBIT) saw $526 million in inflows alone on June 22, he cautioned that such large inflow days have historically preceded BTC price sell-offs.

“As bullish as this is each other time IBIT reported mid-high 9 fig inflow days it occurred around market supply zones,” he summarized.

According to data from sources including United Kingdom-based investment firm Farside Investors, the July 23 netflow total for the US spot ETFs was 533.6 million — the most since March.

At the time, BTC/USD was making all-time highs which still stand, the market having dipped by nearly 25% in the interim.

“So in terms of actually trading this, the obvious part is now does the market sustain this demand & momentum for higher prices,” Skew continued.

He highlighted “consistent” demand for spot, spot takers absorbing supply and overall seller absorption as key requirements to sustain current levels and further upside.

Bitcoin traded at around $66,550 at the time of writing, down 1.5% on the day, per data from Cointelegraph Markets Pro and TradingView.

ETH price flat with hours to ETF launch

Other concerns meanwhile place the Ethereum ETFs in the spotlight.

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Ratified by US regulators to begin trading on July 23, the spot Ether (ETH) products have so far failed to spark an anticipatory run-up in price for the largest altcoin by market cap.

Instead, ETH/USD is up just 1.5% over the past week and flat on the day, marking a significant contrast to Bitcoin in the days before its ETFs went live in mid-January.

“The lack of positive reaction is a negative reaction,” trading firm QCP Capital wrote in part of its latest bulletin to Telegram channel subscribers.

“Market seems to be seeing who folds first to ‘sell the news.’”

As Cointelegraph reported, some see several months being required in order to gauge real demand for spot Ether ETFs.

This article does not contain investment advice or recommendations. Every investment and trading move involves risk, and readers should conduct their own research when making a decision.