Sodastream International shares jumped on Thursday following reports that the company would go private, but investors shouldn't bank on a deal, a financial services firm said.
Stifel called the sale "highly improbable to impossible." The firm said the reported deal of $40 a share would overvalue the company.
It added that any deal would rely heavily on outside capital, noting Sodastream had a negative free cash flow in each of the past three years. Stifel maintained its "sell" recommendation on the company.
Bloomberg reported on Thursday that the maker of home soda machines was in talks with an investment firm to go private, citing sources familiar with the matter. The deal would value Sodastream at $40 a share, or $828 million, a 38 percent premium above Wednesday's close.
After being halted briefly on the Nasdaq, Sodastream shares hovered more than 10 percent higher on Thursday.
— By CNBC staff