Glassmaker Corning made a smart deal Friday. Image: Corning.

Friday closed a tough week for the stock market, with the Dow falling more than 300 points, and other major market benchmarks finishing down around 2% on the day. Concerns about the continued drop in energy prices and their potential impact on the global economy kept weighing on stocks, and the increasing likelihood that 2015 will be the first down year for the stock market since 2008 appeared to make some investors nervous.

Amid the doom and gloom, however, a few stocks still did well. Finisar (FNSR), Summit Midstream Partners (SMLP -0.83%), and Corning (GLW 1.23%) were among the best performers in the market on Friday.

Finisar jumped 22% after posting strong earnings for its fiscal second quarter on Thursday night. The maker of components for optical networking reversed a year-ago loss with a modest GAAP profit. Even though the company's guidance for the fiscal third quarter was weaker than the consensus forecast among investors, shareholders in the beaten-down stock appeared to take solace from the fact that Finisar seems to have hit bottom.

Given how badly Finisar missed expectations in its previous quarter, it makes sense that investors would cheer even mixed results. Nevertheless, Finisar still faces plenty of competition in some of its key markets, and if a broader market downturn leads companies to forego network upgrades, the optical-networking specialist could have trouble keeping up its positive momentum.

Summit Midstream Partners soared 19%. The limited partnership announced that Summit Investments, which controls the owner of Summit Midstream's general partnership interest, would help make possible the continued drop-down of assets into the limited partnership without the need for Summit Midstream to obtain further equity financing. The strategic-review process conducted by the private equity firm that controls Summit Investments also came to the conclusion that drop-down transactions might occur on an accelerated basis, leading to completion of the drop-down plan by the first quarter of next year.

The private equity firm said that the current unit price for Summit Midstream "undervalues the future distribution potential of SMLP," and therefore authorized an additional investment of $100 million. Even though Summit also reduced its guidance for the fourth quarter, investors were pleased at the idea that the limited partnership has an apparent lifeline in a tough environment for raising capital.

Finally, Corning rose 6%. The glassmaker said that partner Dow Chemical (DOW) had agreed to purchase Corning's 50% interest in their Dow Corning joint venture. With Dow Chemical planning a merger that will bulk up its presence in the chemicals industry, the takeover allows it to boost its exposure to the silicone market and products serving the automotive and construction industries.

In exchange, Corning will get a 40% interest in polycrystalline silicon manufacturer Hemlock Semiconductor, as well as $4.8 billion in cash. CEO Wendell Weeks said that, despite Dow Corning's success, the silicone business isn't central to Corning's priorities, and the transaction will help Corning get the most value from its share in the venture going forward.