Cryptocurrencies jumped to start the week as hopeful investors weighed the likelihood that the U.S. will finally see a bitcoin ETF in the coming months.

At one point Monday morning, bitcoin surged above $30,000 in a sudden spike on an unconfirmed report that the iShares spot bitcoin ETF had been formally approved by the Securities and Exchange Commission. But the coin quickly gave up those gains as that report was unable to be confirmed by major media. BlackRock told CNBC the iShares Bitcoin ETP application is still under review by the SEC. Sources close to the SEC said that Monday's report was not accurate.

In recent trading, bitcoin rose about 5.28% to $28,454.17, according to Coin Metrics, while ether added 1.86% to trade at $1,589.10.

Last week, bitcoin had jumped on Friday on news that the SEC would not appeal a ruling in Grayscale's lawsuit against regulators. In June of 2022, Grayscale sued the SEC over its denial of the company's application to convert the popular Grayscale Bitcoin Trust (GBTC) to an ETF.

"The Federal Rules of Appellate Procedure's 45-day period to seek rehearing has now passed. The Court will now issue its final mandate within seven calendar days," a Grayscale spokeswoman told CNBC. "The Grayscale team remains operationally ready to convert GBTC to an ETF upon the SEC's approval, and we look forward to sharing more information as soon as practicable."

It's possible the SEC could again deny Grayscale's request, but the commission has recently been losing momentum in its attempt to broadly regulate crypto, with Grayscale in particular proving an obstacle. For example, the D.C. Court of Appeals called the SEC's denial "arbitrary and capricious." Many investors read Friday's news as a signal that the SEC could be close to allowing Grayscale to list GBTC shares.

"Many people think the fact that the SEC chose to ask questions is a change of behavior and therefore I do think hopes are rising that a or a number of bitcoin ETFs will be approved," Ark Invest CEO Cathie Wood said on CNBC's "Halftime Report" Monday.

To be sure, bitcoin is coming off its worst week since Aug. 18 and first negative week in six. It lost 4.35% for the week, closing at $26,755.66, according to Coin Metrics. Ether lost 6.36% for the week and ended the week at $1,544.24.

Bitcoin and ether may also be benefiting from worries about a recession, which has Paul Tudor Jones last week to Bernstein this morning touting bitcoin as a safe haven trade in an uncertain macroeconomy.

Still, the price of bitcoin is under some pressure as the regulatory uncertainty in the U.S. crypto industry has investors apathetic about boosting their positions. As a result, the market has been plagued by low volume and liquidity and bitcoin has been unable to reach new highs above $30,000.

The optimism Monday morning lifted other crypto assets. Ripple's XRP and Binance Coin, the top coins by market cap behind bitcoin and ether excluding stablecoins, were higher by 1.77% and 2.42%, respectively. Smart contracts platform Solana's sol token was up 9% and Polygon's matic token added 2.8%.

Crypto equities, which have also struggled recently, are outperforming crypto assets. On Monday morning Coinbase was higher by more than 2% in early trading. Mining stocks including Riot Platforms and Marathon Digital, were up about 5% across the board.

— CNBC's Jesse Pound, Nick Wells and John Melloy contributed reporting.

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