FOURTH AMENDMENT TO COMMERCIAL LOAN AGREEMENT AND SECURITY AGREEMENT

EXHIBIT 10.1

FOURTH AMENDMENT TO
COMMERCIAL LOAN AGREEMENT
AND
SECURITY AGREEMENT

     This FOURTH AMENDMENT TO COMMERCIAL LOAN AGREEMENT and SECURITY AGREEMENT, dated as of February 13, 2007 (this “Fourth Amendment”), is between VERICHIP CORPORATION, a Delaware corporation (the “Borrower” or “Debtor”), and APPLIED DIGITAL SOLUTIONS, INC. , a Missouri corporation (the “Lender”).

Recitals :

     WHEREAS, on December 27, 2005, the Borrower and the Lender entered into a Commercial Loan Agreement (the “Agreement”) pursuant to which Lender made a Loan to Borrower subject to the terms and conditions contained in the Agreement;

     WHEREAS, on October 6, 2006, the Borrower and the Lender entered into a First Amendment to Commercial Loan Agreement pursuant to which Lender increased the principal amount of the Loan by Four Million Five Hundred Thousand Dollars ($4,500,000.00) (including a change in the applicable interest rate) in order to meet the Borrower’s working capital needs, IPO costs, and cash needs in connection with Perceptis’ potential election to take its final (deferred) payment in cash and to make certain other amendments to the Agreement contained herein;

     WHEREAS, on January 19, 2007, the Borrower and the Lender entered into a Second Amendment to Commercial Loan Agreement pursuant to which Lender increased the principal amount of the Loan by One Million Five Hundred Thousand Dollars ($1,500,000.00) in order to meet the Borrower’s working capital needs and IPO costs;

     WHEREAS, on February 8, 2007, the Borrower and the Lender entered into a Third Amendment to Commercial Loan Agreement, a Third Amended and Restated Revolving Line of Credit Note, and a Third Amendment to Security Agreement, pursuant to which certain payment terms were changed and the revolving nature of the Loans would be deemed changed upon the occurrence of certain events; and

     WHEREAS, the Lender and the Borrower desire to clarify certain terms now existing under the Loan Documents;

     NOW THEREFORE, in consideration of the mutual covenants and agreements set forth herein, and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties agree as follows:

Agreement.