Two prominent crypto asset managers — Grayscale Investments and Bitwise Asset Management — have halted their Ether (ETH) futures exchange-traded fund (ETF) plans amid growing scrutiny from United States regulators.

On May 17, Grayscale filed an amendment to its Securities and Exchange Commission (SEC) filing to remove mentions of an Ether futures ETF. The amendment comes less than a week after sharing plans to launch a trio of ETF products. The other two flagship products include a semi-spot Bitcoin (BTC) ETF that would invest in the spot BTC market, and a privacy ETF focused on investing in privacy-focused blockchain companies and digital assets.

Grayscale’s amendment to its ETF filing came just days after SEC asked the asset manager to pull its application for a Filecoin Trust. The regulatory body warned that its underlying asset, Filecoin (FIL), qualifies as a security.

Grayscale responded to the SEC’s accusation, claiming the underlying asset does not qualify as a security. The firm “intends to respond promptly to the SEC staff with an explanation of the legal basis for Grayscale’s position.”

Bitwise, on the other hand, has withdrawn its application to launch an ETH-based futures ETF altogether. In its amendment filing with the SEC on May 17, the crypto asset manager claimed that it doesn’t “intend to seek effectiveness of the fund and no securities of the fund was sold, or will be sold, pursuant to the above-mentioned post-effective amendment to the trust’s registration statement.”

Related: GBTC approval could return a ‘couple billion dollars’ to investors: Grayscale CEO

Bitwise didn’t respond to Cointelegraph’s request for comments on the issue by the time of publication.

A Bitcoin-based futures ETF debuted in the last quarter of 2021, making many in the crypto industry believe that a spot crypto ETF is on the way. However, after two years and a barrage of crypto carnages in 2022, regulators have grown more skeptical of such products.

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