A hedge fund run by billionaire David Tepper is seeking clarification in the way SunEdison (NYSE: SUNE) is managing its yieldco, triggering a huge plunge in the company shares and casting a shadow over broader solar-sector exchange traded funds.

On Tuesday, the Guggenheim Solar ETF (NYSEArca: TAN) and the Market Vectors Solar Energy ETF (NYSEArca: KWT), which track global solar photovoltaic panel producers, declined 4.2% and 3.6%, respectively.

Meanwhile, SUNE was down 23.6% mid-Tuesday after plummeting as much as 34% in earlier trading. SunEdison makes up 7.0% of TAN and 5.1% of KWT.

SunEdison shares retreated the most in a month after Appaloosa Management sought documents from TerraForm Power Inc on the recent management shift and on acquisitions the parent company negotiated, reports Chris Martin for Bloomberg.

The hedge fund is accusing TerraForm’s management of acting more in interest of SunEdison than shareholders.

TerraForm Power is a yieldco tied to Sunedison, the country’s largest developer of renewable energy. SunEdison was the first solar company to launch a yieldco in July last year – a yieldco is a dividend growth-oriented company that groups renewable or conventional long-term contracted operating assets to generate steady cash flows for investors. [SunEdison Casts A Cloud On Solar ETFs]

Concerns arose after SunEdison’s acquisition of Vivint Solar and sell shares in second holding company, TerraForm Global. Appaloosa is now asking for all documents related to the transaction and management changes.