By Jonathan Moreland, founder of Insider Insights and author of Profit From Legal Insider Trading.

NEW YORK ( TheStreet) -- It is a victory for common sense. Tracking the trading behavior of company executives, directors and large shareholders in the stocks of firms they're registered in as "insiders" has proven to be profitable, according to both academic studies and (more importantly) the experience of professional investors.

Below are lists of the top 10 mainly open-market insider purchases and sales filed at the Securities and Exchange Commission Thursday, May 9, 2013, as ranked by dollar value. Please note, however, that these are only 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.

At, 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.

So use these regular Top Insider Trades columns as the initial research tools they are meant to be, and click the links in the tables to analyze a company's or insider's full insider history. Also feel free to contact us with any questions on our proprietary insider data, and how it is best analyzed.
Abiomed (ABMD) Termeer Henri A DIR 100,000 1,986,410
Iberiabank (IBKC) Cooper Angus R II DIR 10,000 464,059
Walter Energy (WLT) Tokarz Michael T DIR 25,000 443,750
Eckert Thomas D DIR 300 300,009
Opko Health (OPK) Frost Phillip Md CEO,CB,BO 42,000 281,030
NB Hi Yld Str (NHS) Benjamin Ann H O 17,395 249,677
US Steel
Gerber Murry DIR 12,925 239,094
Calamos Asset (CLMS) Calamos John P CB,CEO,BO 14,832 163,143
Prolor Biotech (PBTH) Frost Phillip Md DIR,BO 25,400 157,348
Ind Bank
Smith G Stacy DIR 5,427 157,048
Source: Insider Insights
Fleetcor (FLT) Balson Andrew DIR 1,595,986 129,274,864
Google (GOOG) Brin Sergey F,DIR,BO 83,334 71,423,288
Moodys (MCO) Berkshire Hathaway BO 371,361 23,788,198
Linkedin (LNKD) Hoffman Reid DIR,BO 83,334 14,963,006
TCF Fin (TCB) Cooper William A CB,CEO,DIR 500,000 7,500,000
Linkedin (LNKD) Weiner Jeff CEO,DIR 37,000 6,643,652
Servicenow (NOW) Luddy Frederic B DIR 127,145 5,052,590
Equinix (EQIX) Taylor Keith D CFO 17,500 3,745,000
Dct Ind Tr (DCT) Wattles Thomas CB,DIR 376,895 3,111,268
Jacobson Mitchell DIR,BO 30,000 2,424,150
Source: Insider Insights

Key to Titles: A=Assistant, AI=Affiliated Investor, AO=Accounting Officer, BD=Business Development, BO=Beneficial Owner, CAO=Chief Accounting Officer, CB=Chairman, CCO=Chief Compliance Officer, CEO=Chief Executive Officer, CFO=Chief Financial Officer, CIO=Chief Information Officer, CO=Compliance Officer, COO=Chief Operating Officer, CT=Controller, CTO=Chief Technology Officer, DIR=Director, EVP=Executive Vice President, F=Founder, FO=Financial Officer, GC=General Counsel, HR=Human Resources, IO=Information Officer, IR=Investor Relations, LO=Legal Officer, MD=Managing Director, O=Officer, OO=Operating Officer, PR=President, PT=Partner, REL=Relative of an insider, SEC=Secretary, SH=Shareholder, SO=Sales Officer, TO=Technology Officer, TR=Treasurer, TT=Trustee, VCB=Vice Chairman, VP=Vice President, X=Ex Officer or other title displayed.

Jonathan Moreland is the founder of, which produces a weekly newsletter and offers professional screening and alerting tools to analyze a proprietary, real-time insider data feed. He is also the principal of Insider Asset Management, a registered investment advisor in New York. Mr. Moreland has been analyzing insider data professionally for two decades and has been a contributor to since 2001. A fundamental analyst with an MBA in finance, Mr. Moreland long ago identified insider data as an excellent first screen to determine where to focus his research efforts. He is quoted frequently in the media for his insider analysis and stock recommendations stemming from it. He is also author of Profit From Legal Insider Trading.

Under no circumstances does the information in this column represent a recommendation to buy or sell stocks. While he cannot provide investment advice or recommendations, Moreland appreciates your feedback; click here to send him an email.