Company: MTZ
Filing Date: 2025-02-28
Form Type: S-3ASR
Source: 0001193125-25-042499
Chunk: 42

Company: MASTEC INC
Filing Date: 2025-02-28
Form: S-3ASR
Chunk 42
---
secure the obligations of holders of stock purchase contracts to purchase the underlying security or property under the related stock purchase contracts. The rights of holders of stock purchase contracts to the related pledged securities will be
subject to our security interest therein created by the pledge agreement. No holder of stock purchase contracts will be permitted to withdraw the pledged securities related to such stock purchase contracts from the pledge arrangement.

An applicable prospectus supplement will describe the terms of the stock purchase contracts, including, if applicable, collateral or
depositary arrangements.

31

SELLING SECURITY HOLDERS We may from time to time register for resale hereunder certain of our securities held by particular selling security holders. In the event we effect such a registration, we will file a prospectus supplement that includes:

| • |     | the names of the selling security holders; |

| • |     | the class and quantity of our securities offered by each selling shareholder; |

| • |     | the number or amount of such securities held by each selling security holder before and after the offering; |

| • |     | the percentage (if one percent or more) of such class of securities held by each selling security holder before 
 and after the offering;                                                                                         |

| • |     | the nature of any position, office or other material relationship that each selling security holder has had with 
 us or any of our predecessors or affiliates within the last three years;                                         |

| • |     | any other applicable terms of the securities offered by each selling security holder; and |

| • |     | the plan of distribution with respect to securities to be offered by the selling security holders. |

32

PLAN OF DISTRIBUTION We may sell securities to one or more underwriters or dealers for public offering and sale by them, or we may sell the securities to investors directly or through agents. The applicable prospectus supplement will set forth the terms of the particular offering and the method of distribution and will identify any firms acting as underwriters, dealers or agents in connection with the offering, including:

| • |     | the name or names of any underwriters; |

| • |     | the respective amounts underwritten; |

| • |     | the nature of any material relationship between us and any underwriter; |

| • |     | the nature of the obligation of the underwriter(s) to take the securities; |

| • |     | the name or names of any selling security holders; |

| • |     | the purchase price of the securities; |

| • |     | any underwriting