Tesla investor Cathie Wood says she's been selling Nvidia stock for some time: 'It has become a check-the-box stock'

• Cathie Wood says Nvidia "has become a check-the-box stock."
• Wood says she's been selling the stock because "expectations could be getting ahead of themselves."
• The semiconductor giant's market capitalization surpassed Amazon's and Alphabet's last week.

Ark Invest's Cathie Wood says she's been selling Nvidia stock because she thinks it's become overvalued.