Image source: LinkedIn.

What: Shares of LinkedIn (LNKD.DL) have fallen 15.2% so far in 2016, according to data from S&P Global Market Intelligence. Yes, that includes a quick 45% boost when Microsoft (MSFT 0.23%) stepped in to buy the company at a generous acquisition premium.

So what: The Microsoft deal was done in the wake of an equally game-changing 45% drop on one cold day in February, following a solid fourth-quarter report with a side of disappointing forward guidance.

That report left LinkedIn looking like a former growth stock, and investors were quick to remove premium-level valuation multiples from the shares. Stock prices fell as low as 4.5 times trailing sales. Microsoft took advantage of these historically low ratios to grab LinkedIn at a discount. It's not every day you can offer a 45% price premium and still pay 15% of the going rate just five months earlier.

Now what: Assuming the Microsoft offer survives the usual battery of shareholder and regulatory closing procedures, this is the end of LinkedIn as a stand-alone business. It's unclear exactly why Microsoft is interested in owning LinkedIn, since the two companies don't have much in common.

Microsoft's press statements focused on LinkedIn's rapid growth and hinted at integrating the platform into Microsoft Office 365.

Either way, there's no reason to own LinkedIn shares today. The stock already trades at 97% of Microsoft's final offer, leaving little room for arbitrage in a positive direction. If the deal runs into roadblocks and falls apart, there's plenty of space for a big price drop.

Lots of risk, no reward -- it's time to sell your LinkedIn shares and stay away.