SINA (SINA) stock is down over 20% over the past year, continuing a downturn that started about two years ago. While there are plenty of reasons to remain bearish on China's main Twitter-like service, there are just as many reasons to be bullish about SINA's profit-earning potential over the long term.

In the video below, Fool contributor Kevin Chen details three key reasons:

  1. SINA's basically a big start-up with a risk-taking culture. It's not afraid to experiment as evidence by two new ventures.
  2. SINA has struck a key partnership with Apple. Now, once China Mobile (CHL) begins subsidizing Apple's (AAPL -0.57%) iOS devices, SINA is sure to benefit.
  3. SINA has joined with Baidu to help power the search giant's cloud services and mobile operating system. While Baidu (BIDU 1.24%) has hit a rough patch, the company is still the 800-pound gorilla in the room, so once Baidu's fortunes improve, SINA is well positioned to skyrocket, too.

To learn more about the bullish case for SINA, watch the video below.