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

NEW YORK ( TheStreet) -- Which insiders are selling and buying chunks of stocks?

Below are lists of the top 10 mainly open-market insider purchases and sales filed at the Securities and Exchange Commission Tuesday, Dec. 20, 2011, as ranked by dollar value. Company executives and directors are in the best position to assess the attractiveness of their firms' shares, and here is how many of them are voting their wallets! 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.

Texas Industries (TXI) NNS Holding BO 183,800 $5,278,146
Acadia Healthcare Company (ACHC) Waud Reeve B DIR,BO 366,666 $2,749,995
United Therapeutics (UTHR) Rothblatt Martine A CEO,DIR 11,823 $519,212
Doral Financial (DRL) Wakeman Glen PR,CEO
735,835 $496,247
Idexx Laboratories (IDXX) Murray Robert J DIR 6,500 $484,520
Hampshire Group (HAMP) Woodward Peter H DIR 100,000 $225,000
Support.Com (SPRT) RgGM Capital BO 114,900 $216,587
Pioneer Southwest Energy LP (PSE) Hall Frank W VP,CAO 7,500 $195,143
Apache (APA) Montgomery William C DIR 2,000 $177,430
CNO Financial (CNO) Long Roger Keith DIR 25,000 $142,758
Primerica (PRI) Mason Mark DIR 8,081,542 $175,183,584
Autozone (AZO) Lampert Edward S BO 421,887 $137,371,152
Constellation Energy Partners (CEP) Constellation Energy Group BO 2,790,224 $5,998,982
Garmin Ltd (GRMN) Eller Donald DIR 100,000 $3,818,721
Primoris Services (PRIM) Rosenfeld Eric DIR 226,576 $3,373,404
Liberty Global (LBTYA) Bracken Charles H R VP,CFO 60,851 $2,375,399
Tutor Perini (TPC) Tutor Ronald N CB,CEO
150,000 $1,888,633
Lululemon Athletica (LULU) Wilson Dennis J DIR,BO 25,000 $1,135,323
Gen Probe (GPRO) Nordhoff Henry L DIR 20,000 $1,127,030
Idexx Laboratories (IDXX) Ayers Jonathan W CB,PR
15,000 $1,104,538

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.