Apple stock underperforms SP500 for an year and half. The severe underperformance comes despite a huge buy back program. Between 2015 and 2016 the company has spent almost $90 billion to buy it's own stock. The stock float was reduced by 12% over the period. Despite the efforts the stock price dropped 34% from the all time high.
The company is a darling (and their best shot at investment) of large sovereign funds and hedge funds. Among the stock holders are Norway with at least $5 billion invested, Swiss National Bank with at least $1 billion, Israel central bank with at least $100 million stake and the list goes on. The company is one of the top three most popular stocks among hedge funds. For example, a stake of Black Rock in the company is at least 3% of the float. Short interest in the AAPL stock is relatively low at 1% of the float or 2 days of trading volume.
Now the scary part. A weekly trading volume in AAPL stock is hovering near multi years lows. If a large fund decides for any reason to raise cash the investors can discover that the doors are too narrow to exit.