In a victory for common sense, the trading behavior of company executives, directors, and large shareholders in the stocks of firms they're registered "insiders" at have been proven profitable to monitor by both academic studies and (more importantly) the experience of your fellow professional investors.

Below are lists of the top 10 mainly open-market insider purchases and sales filed at the Securities and Exchange Commission Monday, February 11, 2013 as ranked by dollar value.

Please note, however, that these are factual lists, not buy and sell recommendations. Dollar value is only one metric to assess the importance of an insider transaction, and, frankly, often not even the most important metric that determines if an insider transaction is significant.

In insider purchases, the data storage products and services corporation EMC (NYSE:EMC) bought $19,958,390 worth of stock in  VMware (NYSE:VMW). At molecular diagnostics company Genomic Health (NASDAQ:GHDX), which develops genomic-based clinical laboratory services for studying the biology of cancer, Director Felix Baker bought $3,275,190 worth of company stock. F. Thomson Leighton, CEO of Akamai Technologies (NASDAQ:AKAM), which provides content delivery and cloud infrastructure to companies, bought $1,765,500 worth of company stock.

In insider sales, global investment holding company Dubai Holding, a beneficiary owner of investment manager Och-Ziff Capital Management Group (NYSE:OZM), sold $49,395,260 worth of company stock. Sumner Redstone, Chairman of Viacom (NASDAQ:VIAB), sold $7,558,562 worth of company stock. At LinkedIn (NYSE:LNKD), CFO and Senior Vice President Steven Sordello sold $5,716,799 worth of company stock. J. Randall MacDonald, Senior Vice President of Human Resources at IBM (NYSE:IBM), sold $4,844,597 worth of company shares.
 
At InsiderInsights.com, we find new investment ideas just about every day using these and more intricate insider screens to determine where we should focus our subsequent fundamental and technical analysis. And while stocks don't (or shouldn't) move up or down based on insider activity alone, insiders tend to be good indicators of when real stock-moving events like earnings surprises, corporate actions, and new products may be in the offing.

Insider Purchases

#:	Filer Name	Insider Titles	Company Name	Ticker	Trans Type	Dollar Value
1	EMC	BO	VMware	VMW	B	$19,958,390
2	Baker Felix	DIR,BO	Genomic Health	GHDX	B	$3,275,190
3	Leighton F Thomson	CEO,DIR	Akamai Tech	AKAM	B	$1,765,500
4	RGM Capital	BO	Guidance Software	GUID	B	$1,260,660
5	Frost Phillip MD	CEO,CB,BO	Opko Health	OPK	B	$696,818
6	Miller Lloyd I	BO	Trans World	TWOC	B	$588,938
7	Twin Haven Sp Op Fd	BO	Hawaiian Telcom	HCOM	B	$171,243
8	King Stephen V	DIR	First Busey	BUSE	B	$117,397
9	Zelter James C	CEO,DIR	Apollo Investment	AINV	B	$83,497
10	Ballantyne Tad M	DIR	Life Partners	LPHI	B	$71,920

Source: InsiderInsights.com | Key to Insider Title and Trans Type Codes

Insider Sales

#:	Filer Name	Insider Titles	Company Name	Ticker	Trans Type	Dollar Value
1	Dubai Holding	BO	Och Ziff Cap	OZM	S	$49,395,260
2	Redstone Sumner M	CB,DIR,BO	Viacom	VIAB	JS*	$7,558,562
3	Ryan Vincent J	DIR	Iron Mountain	IRM	AS	$6,559,540
4	Sordello Steven J	VP,CFO	Linkedin	LNKD	AS	$5,716,799
5	Macdonald J Randall	VP	IBM	IBM	S	$4,844,597
6	Hurwitz Even	VP	Philip Morris Intl	PM	S	$4,038,750
7	Homfray Christopher	VP	Crown	CCK	S	$3,522,096
8	Hart Steven R	CTO	Viasat	VSAT	AS	$3,310,000
9	Danziger Eric A	PR,CEO	Wyndham Worldwide	WYN	S	$2,984,788
10	Levine Leichtman Cap	BO	Consumer Portfolio	CPSS	S	$2,814,629

Source: InsiderInsights.com | Key to Insider Title and Trans Type Codes

Editor's note: Jonathan Moreland is the founder of Insider Insights and author of "Profit From Legal Insider Trading."