The iPad maker’s shares declined another 2.5 percent on Friday to finish near $573 a share. This is the eighth out of the last nine trading sessions that the stock has traded in negative territory.

Apple’s seen a stellar run this year, surging more than 40 percent to hit its all-time high of $644 on April 10. The firm also became the world’s most valuable company, when its market cap first crossed $600 billion.

“[The stock] is way up and people think it has risk," said Art Cashin, director of floor operations at UBS Financial Services. "The real risk is if people say: 'It’s had a great ride, I’m going to take profits.' I think you’re seeing some of that.”