He warned that the "rainmaker is gone" and that the company's new suite of products haven't been very innovative.
But Gundlach's thesis goes beyond just Apple's ability to offer new products and maintain earnings growth,
Another big problem for Apple is the fiscal cliff.
During a September presentation, Gundlach noted that capital gains tax rates are scheduled to go up as Bush-era tax cuts expire. He argued that this could be particularly problematic for Apple and other stocks that have generated huge paper gains for investors because the incremental tax would represent a big dollar cost.
Investors who have been looking for an opportunity to make their exit may be exiting now.
Here's a long-term look at Apple, which is up a staggering 14,000 percent in the last 10 years.
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