U.S. stocks were lower Tuesday, with investors weighing the latest developments on the trade front to kick off a seasonally poor month for equities. Rising yields also worried investors.

Nvidia fell 3%, TSMC fell 2%.

The moves come after a federal appeals court on Friday ruled that most of President Donald Trump’s global tariffs are illegal. The U.S. Court of Appeals for the Federal Circuit determined in a 7-4 ruling that only Congress has the authority to apply sweeping levies. Trump called the decision “Highly Partisan” and has said that he will appeal the ruling to the U.S. Supreme Court.

Investors were also eying a surge in bond yields to start September. The 10-year Treasury yield jumped to 4.29%, while the 30-year yield topped 4.98%.

Bond investors were driving yields higher on the prospect that the U.S. may have to refund the billions brought in from tariff revenue, worsening the country’s already-stressed fiscal situation.

Those developments could weigh on sentiment to start a new trading month. September is historically the worst month for equities, with the S&P 500 averaging a 4.2% drop over the last five years, and falling more than 2% on average over the last 10.

Wall Street is coming off a strong month for the stock market. In August, the 30-stock Dow advanced more than 3%. The S&P 500 rose nearly 2%. The tech-heavy Nasdaq ended the month 1.6% higher. It was the fourth month in a row of gains for the S&P 500. The big event traders are waiting for is the release of August’s jobs report on Friday and how it will influence the Fed’s interest rate decision coming mid-month.

August saw the S&P 500 add five new all-time highs, putting the index’s year-to-date total at 20, Sam Stovall of CFRA Research noted.

“For those years in which the S&P 500 tallied 20 or more new highs through the end of August, the S&P 500 continued to post an average decline in September,” the firm’s chief investment strategist said. “The market may surrender some recent gains in the near term as it awaits new catalysts.”