During challenging times for the stock market, one investor has historically found ways to make the most of difficult investing conditions. Warren Buffett has led Berkshire Hathaway (BRK.A 0.64%) (BRK.B 0.54%) for decades, producing market-beating returns and often dramatically outperforming the broader stock indexes during bear markets and other downturns.

Every quarter, Berkshire Hathaway has to report to the U.S. Securities and Exchange Commission (SEC), disclosing many of the stock holdings it has. The most recent report came out late Monday, and it revealed two new Warren Buffett stocks that are worth a closer look.

1. Taiwan Semiconductor Manufacturing

The biggest new position for Berkshire Hathaway was Taiwan Semiconductor Manufacturing (TSM -4.86%). The 13F filing with the SEC revealed a position of more than 60 million shares of the semiconductor chip foundry, which was worth more than $4 billion as of the Sept. 30 date of the filing.

Taiwan Semi has built an impressive business model that has caught on across the industry. In the past, many semiconductor design companies maintained in-house foundries to produce physical chips. This involved substantial capital expenditures and distracted from their focus on design innovations. As an alternative, Taiwan Semi chose to specialize in foundry services, essentially acting as a third-party manufacturer to make physical chips based on its customers' designs. Chip designers have flocked to take advantage, and Taiwan Semi now makes more than half of the industry's semiconductors. Moreover, it has even higher market share among the cutting-edge designs that command the highest prices for its chip-designing clients.

The stock has struggled, though, in part because of the cyclical nature of the semiconductor industry. Yet Taiwan Semi has used its commanding position in the chip supply chain to hold its customers to contractual commitments. That helped it boost its third-quarter revenue by 36% year over year, and the company expects consistent strong sales and earnings growth for the rest of 2022 and beyond.

Taiwan Semi's shares jumped more than 10% in premarket trading on Tuesday morning as investors saw Buffett's purchase as a potential end to the long decline in semiconductor stocks more broadly. Whether that proves to be the case remains to be seen, but Berkshire clearly sees value in Taiwan Semi's particular role within the industry.

2. Louisiana-Pacific

Buffett's position in Louisiana-Pacific (LPX -1.00%) was considerably smaller than the Taiwan Semi position, as Berkshire's holdings in the timber and building products company amounted to less than $300 million as of the end of the third quarter. However, Louisiana-Pacific is much smaller than Taiwan Semi, and so the nearly 5.8 million share position Berkshire now has represents about 6.7% of the entire company's outstanding stock.

Louisiana-Pacific has seen extremely strong cyclical demand for its products start to ease recently, although it has done a good job of making the most of its opportunities. In the third quarter, net sales were down 16% from year-earlier levels, with a 35% drop in sales of oriented strand board (OSB). However, Louisiana-Pacific's siding solutions segment picked up the slack, seeing revenue growth of 27%. Nevertheless, income from continuing operations fell by more than 60% year over year, and Louisiana-Pacific expects the strong trends in siding and weakness in OSB to continue into the end of the year.

Longer-term, though, Louisiana-Pacific should benefit from structural shortages in housing stock in the U.S. market. Moreover, with many homebuilders looking for ways to ensure supplies of key materials, the building products specialist is in a strong position even as macroeconomic conditions point to a potential short-term slowdown in housing.

Louisiana-Pacific shares also got a big boost from the news, climbing nearly 10% in premarket trading Tuesday morning. That's actually enough to help it recover much of the ground it has lost since the beginning of the year.

Looking ahead

One key thing to remember about 13F filings is that they are necessarily backward looking. Companies have 45 days to report their holdings as of the end of the quarter, and so even on the same day that Berkshire releases its filing to the public, it's already out of date and potentially no longer reflects Buffett's latest thinking.

That said, Buffett tends to be a long-term investor, and often, Berkshire Hathaway has continued to add to positions in subsequent quarters following the initial appearance of a stock. That's clearly what shareholders in Taiwan Semi and Louisiana-Pacific hope will happen this time around, given the immediate reaction in their stock prices. Often, following Buffett's picks has been a winning strategy for other investors as well.