Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of China-based wealth management specialist Noah Holdings (NYSE: NOAH) crashed in intraday trading to an 11.9% drop at worst, then rebounded to a 6.8% gain at the top and now trade roughly where they were after Friday's closing bell.

So what: With no company-specific news in circulation, all evidence points to manipulative trading in this case, either by robotic algorithms or a deft human hand. Normally shifting hands in small batches of a couple hundred shares at a time, Noah saw a few more substantial trades clearing out the order book at about 10:20 a.m. Eastern time -- and then a massive order for 49,000 shares taking advantage of near-bottom prices.

Now what: Noah is a thinly traded stock at the best of times, which is ironic considering the line of business the company is in. That mega order covers about one-third of an average day's total trading volume, and shows how easily a well-heeled investor can wreak havoc on low-volume stocks. Unless you truly have unique insights into why Noah would be a superior stock to own in spite of these shenanigans, you'll probably be happier owning American counterparts such as Bank of New York Mellon (NYSE: BK), Ameriprise Financial (NYSE: AMP), or Kohlberg Kravis Roberts (NYSE: KKR), all of which sport between 10 and 100 times the trading volume of Noah -- and are orders of magnitude more difficult to manipulate.

Interested in more info on Noah Holdings? Add it to your watchlist.