MASTEC INC — Director's Dealing 2007

Dec 20, 2007

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MASTEC INC (MTZ)
CIK: 0000015615
Period of Report: 2007-12-18

Reporting Person: SHANFELTER AUSTIN J (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2007-12-18	Common Stock	S	30000	$9.91	Disposed	342349	Direct
2007-12-20	Common Stock	S	15671	$9.91	Disposed	326678	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2007-12-18	Forward Sale Contract (obligation to sell)	$	J	150000	Acquired	2007-12-18	Common Stock (150000)	Direct
2007-12-20	Forward Sale Contract (obligation to sell)	$	J	150000	Acquired	2007-12-20	Common Stock (150000)	Direct

Footnotes

F1: The sales reported in this Form 4 were pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on June 4, 2007, as amended. The original trading plan was established to sell up to 120,000 shares of Mastec, Inc (the "Company") common stock at three ascending price levels from $13 to $17 per share. The plan was amended on December 4, 2007, to sell the 25,000 remaining shares in the plan at a price of $9.00 per share or better. The plan amendment also added an additional 20,671 shares to sell at a price of $9.00 per share or better. All of the shares subject to the plan have now been sold.

F2: The sales were executed in eighteen (18) separate transactions with sales prices ranging from $9.76 to $10.09 for a weighted average sales price of $9.91

F3: The sales were executed in eighteen (20) separate transactions with sales prices ranging from $9.83 to $10.01 for a weighted average sales price of $9.91.

F4: On December 6th, 2007, Mr. Shanfelter exercised options for 300,000 shares of the Issuer's common stock for a consideration of $1,662,000. On December 18th, 2007, Mr. Shanfelter entered into a type of prepaid variable forward sale contract with an unaffiliated third party under which he received an immediate cash payment of $1,295,568.14. In return, Mr. Shanfelter was obligated under the contract to deliver to such third party up to 150,000 shares of the Issuer's common stock on December 19th, 2009, the maturity date of the contract. Mr. Shanfelter pledged 150,000 shares of MTZ common stock to secure his obligations under the contract, but retained dividend and voting rights in the Pledged Shares during the term of the pledge. The actual number of shares of common stock to be delivered at the maturity of the contract will be determined on the basis of the market price, with a threshold appreciation price of $14.85 per share of the common stock on the maturity date.

F5: On December 20th, 2007, Mr. Shanfelter entered into a type of prepaid variable forward sale contract with an unaffiliated third party under which he received an immediate cash payment of $1,218,365.75. In return, Mr. Shanfelter was obligated under the contract to deliver to such third party up to 150,000 shares of the Issuer's common stock on December 28th, 2009, the maturity date of the contract. Mr. Shanfelter pledged 150,000 shares of MTZ common stock to secure his obligations under the contract, but retained dividend and voting rights in the Pledged Shares during the term of the pledge. The actual number of shares of common stock to be delivered at the maturity of the contract will be determined on the basis of the market price, with a threshold appreciation price of $13.96 per share of the common stock on the maturity date.