For those on Wall Street who thought a controversial proposed tariff on solar panels might indirectly benefit Sunrun Inc., Ed Fenster just burst your bubble.

“There are definitely no benefits to us,” Fenster, the national rooftop solar installer’s chairman, said in an interview Thursday at Bloomberg’s office in San Francisco. Sunrun has fallen about 20 percent and fellow rooftop company Vivint Solar Inc. 23 percent over the past month.

In a case that threatens to roil the $29 billion U.S. solar industry, U.S. International Trade Commission ruled last month that the U.S. solar industry has been harmed by a flood of cheap imports. President Donald Trump may decide to impose tariffs by mid-January. Some analysts had speculated that Sunrun could ultimately benefit because higher prices may show customers are willing to pay more for the panels.

“It’s a farce,” Fenster said. “The data shows clearly that a tariff here not only obviously causes great detriment to the installation of solar and solar installation jobs, but it actually eliminates more manufacturing jobs than it creates.”