Investors ended last week on a fearful note, but hope returned Monday morning as the Dow Jones Industrials (DJINDICES:^DJI)gained 115 points as of 11 a.m. EDT. Most of the attention in the market went to a huge potential merger involving one of the Dow's pharma powerhouses buying out a British counterpart. But looking beneath the M&A fold, you'll also find that IBM (NYSE:IBM) and Microsoft (NASDAQ:MSFT) helped the blue-chip index jump with sharp gains of their own.

The good news that Microsoft shares up 2.9% came from an unexpected source: the U.S. Supreme Court. This morning, the nation's highest court chose not to grant certiorari to a 10-year-old case against Microsoft from Novell, which asserted that Microsoft had wielded monopoly power in choosing not to share some proprietary details of its Windows 95 operating system. Novell, which owned the competing WordPerfect word-processing software for a couple of years during the 1990s, argued that by withholding that information, Microsoft gave an unfair competitive advantage to its Word and other office software. The Supreme Court's decision leaves an appeals-court decision against Novell intact, and more importantly marks an end to another antitrust-related episode in Microsoft's checkered past.

Meanwhile, IBM jumped 2%, with its upward move having even more influence in pushing the Dow higher because of its high share price. The tech giant announced that it would try to bridge an information gap between its cloud services and its customers by launching a cloud marketplace. IBM's move responds to similar offerings by other cloud-computing companies and should help Big Blue's current and potential future customers get a better sense of what IBM service offerings can do to address their specific needs. IBM hopes that by making its services more readily available, customers will find them more easily, take greater advantage of them, and learn about them in a way that will encourage sales in the future. If it works, IBM's cloud marketplace could produce more of the high-margin services revenue that the company will rely on for profit growth in an environment in which sales growth has been hard to find.

M&A activity always has a quick impact on markets, but it's smart to look beyond those headlines at other stocks that are moving Wall Street. That way, you can decide whether market gains are sustainable or just a one-time aberration.

Dan Caplinger has no position in any stocks mentioned. The Motley Fool owns shares of International Business Machines and Microsoft. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.