What happened

Shares of Sierra Wireless Inc. (NASDAQ:SWIR) climbed 16% on Wednesday despite no company-specific news.

So what

Sierra Wireless had no new press releases, SEC filings, insider purchases, acquisition rumors, or analyst upgrades that might otherwise be credited with driving the stock higher today. But the move did come on unusually high trading volume of 1.67 million shares, or roughly four times Sierra Wireless' daily average.

This, perhaps, could indicate that a large, yet-to-be-disclosed investor may have opened or bolstered their stake in the company -- something that could be revealed via Sierra Wireless' Form 4 filings with the SEC should the position be large enough to merit disclosure. And it would be hard to blame them on the heels of Sierra Wireless' impressive first-quarter 2017 results announced last month.

Sierra Wireless logo.

IMAGE SOURCE: SIERRA WIRELESS

Now what

Not every move in the stock market has an easy explanation. But it's not unusual to see small-cap stocks like Sierra Wireless endure volatility on any given day, though such moves generally aren't quite as pronounced as today's climb. Perhaps the underlying driver will become clear in the coming days. In the meantime, I don't think it requires any action or concern from long-term Sierra Wireless shareholders.

Steve Symington has no position in any stocks mentioned. The Motley Fool owns shares of and recommends Sierra Wireless. The Motley Fool has a disclosure policy.