Where can I find the Ownership information about a stock?

You can find the "Ownership" card on the default Summary tab. 

This card lets you know which type of investor owns a particular stock. You can easily see what percentage of the stock is owned by individual investors vs institutions. 

The ownership tab lists the actual large owners plus insider trades. 

You can view it on the main symbol page as shown below.

Ex-https://seekingalpha.com/symbol/AAPL