Why Bristol-Myers Squibb Stock Plunged in the First Half of 2019

Prescription drug giant Bristol-Myers Squibb (NYSE:BMY) lost an eye-catching 12.8% of its value during the first six months of 2019, according to data from S&P Global Market Intelligence. In fact, Bristol's shares broke through their five-year low last April, underscoring just how poorly this big pharma stock has performed so far this year.

What's behind this breathtaking decline for one of pharma's top names? In short, Wall Street isn't convinced that Bristol's $74 billion acquisition of biotech heavyweight Celgene (NASDAQ:CELG) is a smart move.