Insider buying can be a bullish indicator for a stock and provides another piece of information for investors to weigh when doing investment research. Company executives, board members, and shareholders with stakes exceeding 10% must notify the SEC within two days of their share purchases (and sales). Each week, I take a look at the largest insider purchases in search of investing opportunities with this often positive indicator.

Company Name

Market Cap

No. of Shares Purchased

Value Shares Purchased

CAPS Rating
(out of 5)

MAKO Surgical (Nasdaq: MAKO)

$383 million

600,000

$5.79 million

****

Hain Celestial (Nasdaq: HAIN)

$1.14 billion

213,842

$5.57 million

****

BlackRock (NYSE: BLK)

$32.36 billion

25,000

$4.19 million

***

Sources: Barron's; Motley Fool CAPS.

MAKO board member John Freund bought shares in the company's recent public offering at $9.65 per share. Freund's firm, Skyline Ventures, owns more than 10% of MAKO, which is working to become the Intuitive Surgical (Nasdaq: ISRG) of knee surgery. Freund licensed technology to Intuitive Surgical and was a co-founder of the company, so he has one heck of a track record. MAKO is still losing money, but with only 54 of its robotic surgical systems in operation in the U.S. at the end of the company's third quarter, it has lots of room to run if hospitals and surgeons adopt the technology. MAKO's surgical system, known as the RIO (Robotic Arm Interactive Orthopedic), can also be used for hip surgeries.

Investment partnerships controlled by activist investor Carl Icahn bought more shares in natural foods company Hain-Celestial. Hain's portfolio of brands, including Terra, Garden of Eatin', and Earth's Best, line the shelves of natural foods retailers like Whole Foods. Icahn has been buying shares since May, and gained two seats on the company's board in July. Since the July 7 announcement that Icahn's representatives would join the board, Hain stock is up 32%.

BlackRock board member James Grosfeld bought shares of the company at $167.84 per share. The world's largest asset manager is trading far below its 52-week high of $243.80 per share. Bloomberg reports that billionaire Carlos Slim is also buying shares of the company. 

While Fools should always do their own due diligence, and not blindly follow the insiders, insider buying can point to good places to look for opportunities. For more on the companies mentioned, see:

Fool contributor April Taylor does not own shares of the companies mentioned. BlackRock is a Motley Fool Inside Value recommendation. Intuitive Surgical and MAKO Surgical are Motley Fool Rule Breakers selections. Whole Foods Market is a Motley Fool Stock Advisor pick. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.