The stock market continued to do well Wednesday morning, as investors were generally upbeat about the prospects for compromise in Washington and a favorable resolution to trade disputes between the U.S. and China. As of 11:45 a.m. EST, the Dow Jones Industrial Average (DJINDICES:^DJI) was up 74 points to 25,499. Among other major benchmarks, the S&P 500 (SNPINDEX:^GSPC) was higher by 6 points to 2,750, while the Nasdaq Composite (NASDAQINDEX:^IXIC) gained 5 points to 7,420.

Warren Buffett is one of the most famous investors in history, and many people follow Berkshire Hathaway (NYSE:BRK-A) (NYSE:BRK-B) for insight into Buffett's latest vision. Soon, Buffett watchers will be able to get the latest information on recent Berkshire moves. At the same time, Amazon.com (NASDAQ:AMZN) continues to make strategic plays of its own, and the latest could involve a move in a new direction: electric vehicles.

Waiting for Buffett's latest trades

Every three months, institutional investors that manage portfolios have to file a disclosure with the U.S. Securities and Exchange Commission revealing certain positions that they own. Berkshire is just one of many companies that make quarterly filings on Form 13F, and those reports get scrutinized to see what changes have happened with Buffett's portfolio during the three months since the previous quarter's report.

Warren Buffett with others in the background.

Warren Buffett. Image source: The Motley Fool.

Buffett's last report indicated that the Oracle of Omaha was doubling down on Berkshire's holdings in the banking sector. Not only did he add to several positions that Berkshire already owned in the financial sector, but he also bought into some new positions in the sector. Given the relatively low valuations among banks compared to other parts of the market, Buffett's moves were consistent with his value investing approach.

This time around, investors are curious to see what moves Buffett will make. A continued emphasis on banks is a safe bet, but some also wonder how Berkshire will respond to the big share-price decline in Apple, which has become one of the company's most important investments. With the deadline for filing coming later this week, investors won't have to wait too long to see what Buffett thinks are the most promising stocks in the market right now. Berkshire shares are up just a bit today, but its roughly 10% gains since the December market bottom show new confidence among shareholders.

Amazon looks to go mobile -- in another way

Meanwhile, Amazon shares also moved slightly higher in the wake of news surrounding the e-commerce giant. Reports indicate that Amazon is looking to partner with automaker General Motors (NYSE:GM) to make a significant investment in a Michigan-based start-up called Rivian Automotive. Rivian's claim to fame is its work in developing electric pickup trucks, and the reported investment would put a value of roughly $1 billion to $2 billion on Rivian.

For Amazon and GM, an investment of that size isn't all that significant, but it signals a willingness to embrace new vehicle technology and challenge established electric vehicle specialist Tesla. Rivian hopes to start selling its R1T model in late 2020, and while that would give Tesla plenty of time to cement its first-mover advantage, it doesn't force investors to wait long to see the fruits of its investment take shape. For Amazon, staying on the cutting edge of transportation technology is important as it seeks to maximize its options for deliveries in its core e-commerce business while also maintaining the flexibility to pursue unrelated projects. Investors shouldn't be surprised to see the tech giant dipping its toes further into high-tech innovation, and Amazon shareholders can expect further such moves for the foreseeable future.

John Mackey, CEO of Whole Foods Market, an Amazon subsidiary, is a member of The Motley Fool's board of directors. Dan Caplinger owns shares of AAPL and Berkshire Hathaway (B shares). The Motley Fool owns shares of and recommends Amazon, AAPL, Berkshire Hathaway (B shares), and TSLA. The Motley Fool has the following options: long January 2020 $150 calls on AAPL and short January 2020 $155 calls on AAPL. The Motley Fool has a disclosure policy.