What happened

Shares of InterDigital, Inc. (IDCC 0.04%) fell 10% in February 2017, according to data from S&P Global Market Intelligence.

So what

The wireless-technology licensing hub reported strong fourth-quarter results late in the month, but the quarterly report was paired with disappointing guidance for the next quarter. Share prices plunged more than 13% on the news, taking the edge off a strong medium-term rise:

IDCC Chart

IDCC data by YCharts.

InterDigital share prices had more than doubled in 52 weeks prior to the report, and investors can still look back at a market-beating 60% one-year return today.

Now what

InterDigital is making most of its sales and profits from aging 3G and 4G technologies. That's good enough for now, but investors will need the company to stake a serious claim in the upcoming 5G market-share grab. From that perspective, I find it troubling that the company is spending only 10% of its annual revenues on the research and development that should be the lifeblood of any technology specialist worth its salt.

With share prices still sitting close to all-time highs, I'd think twice before buying into this unhealthy combination of market momentum and lackluster R&D efforts.