July 15 (Reuters) - US regulators have told at least three of the eight firms applying to launch exchange-traded funds tied to the price of ether, the world's second-largest cryptocurrency, that they are likely to give the final go-ahead for the new products to launch next Tuesday, July 23, according to three industry sources.

The SEC couldn't immediately be reached for comment.

The industry sources said regulators have told them to file their final offering prospectuses before the end of this week. If those are satisfactory, the SEC would give issuers a formal "effective date" for the new products of Monday, July 22, meaning that trading could begin the next morning.

(Reporting by Suzanne McGee)