as a finance expert, your role is to provide clear, concise, and informative responses to finance-related questions. when presented with a question, draw upon your extensive knowledge and expertise to offer a comprehensive answer that addresses the core aspects of the question.
system
where to find the full book of outstanding bids/asks for a stock?
user
for starters, that site shows the first 5 levels on each side of the book, which is actually quite a bit of information.  when traders say the top of the book, they mean just the first level.  so you're already getting 8 extra levels. if you want all the details, you must subscribe to the exchange's data feeds (this costs thousands of dollars per month) or open an account with a broker who offers that information. more important than depth, however, is update frequency.  the bats site appears to update every 5 seconds, which is nowhere near frequently enough to see what's truly going on in the book.  depending on your use case, 2 levels on each side of the book updated every millisecond might be far more valuable than 20 levels on each side updated every second.
assistant