Image: eBay.

The back-and-forth motion in the stock market on Thursday continued to make investors uncertain about the future direction of their portfolios. Strength in the social-media and energy space bled over into the broader market benchmarks, most of which were up between 0.5% and 1% on the day.

Yet earnings season has shifted into full gear, and as a result, you could find many losing stocks, even on an upward-moving day for the market as a whole. Among Thursday's losing stocks were eBay (NASDAQ:EBAY), Juniper Networks (NYSE:JNPR), and Abbott Labs (NYSE:ABT).

eBay dropped 12% after the online marketplace company reported its fourth-quarter earnings on Wednesday night. Flat revenue and shrinking earnings were largely expected, but the e-commerce retail marketplace provider gave lukewarm guidance for the current quarter, as well.

eBay is still going through some growing pains as it seeks to establish itself as an independent entity after having spun off its electronic payment-processing service as a separate company. Some remain concerned that the company might not emerge victorious in the increasingly cutthroat e-commerce arena, and that could keep weighing on the stock into the future.

Juniper Networks fell 15% in the wake of announcing its preliminary results Wednesday night. The company reported revenue growth and earnings that exceeded what most investors had expected to see, but some of those following the stock took issue with Juniper's first-quarter guidance.

Some investors who are familiar with Juniper noted that the networking-equipment company is prone to give cautious guidance at times of macroeconomic stress, even if it won't necessarily affect its own financial results. Yet because CFO Robyn Denholm also tendered her resignation, many Juniper investors seemed more worried that there could be systemic troubles at the company that could hurt its longer-term growth. Even before today's drop, Juniper was still dealing with challenges that have kept its stock price low since 2011.

Finally, Abbott Labs declined 9%. Thursday morning's fourth-quarter financial report from the medical device and equipment maker featured a 3% drop in sales that helped send net income from continuing operations down 1%, and adjusted earnings from continuing operations were flat from last year's quarter. What investors took issue with was Abbott's guidance, which included earnings projections for the current quarter and full year 2016 that were below expectations.

The strong dollar has hit the internationally focused company hard, and Abbott also faces a particularly tough time in the hard-hit Venezuelan economy, where it has enough exposure to cause problems for the company. Without an evident turnaround in the currency markets, Abbott Labs could remain under pressure for the foreseeable future.

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