MTZ

The purpose of this filing to is report the entry by JM Holdings I on August 10, 2026 into an amendment (the "Fourth Amendment") to the previously reported prepaid variable forward sale contract entered into by JM Holdings I with an unaffiliated party (the "2019 Prepaid Forward Contract," and, as amended to date, the "Prepaid Forward Contract"). The Fourth Amendment amends the Floor Price (as defined below) and Cap Price (as defined below) for each Tranche 1 Component (as defined below), which were determined based on the volume weighted average price (the "VWAP") of MasTec, Inc.'s common stock for a specified period ended on August 11, 2026. The Prepaid Forward Contract provides for the settlement of the transaction, at the option of JM Holdings I, in cash or in Shares. At settlement JM Holdings I will be obligated to deliver to the buyer, on the applicable date in August or September 2027 or 2028 for the applicable component (each, a "Valuation Date") in the first ("Tranche 1") or second ("Tranche 2") tranche, as applicable, of 15 components each ("Tranche 1 Components" or "Tranche 2 Components"), at JM Holdings I's option, up to 100% of the number of Shares pledged for such component or an equivalent amount of cash. JM Holdings I entered into the 2019 Prepaid Forward Contract to provide funds for investment in the Miami Major League Soccer franchise. For more information on the terms of the Prepaid Forward Contract, please see Item 6 below.

The purpose of this filing to is report entry by Jose Ramon Mas on August 10, 2026 into an amendment (the "Fourth Amendment") to the previously reported prepaid variable forward sale contract entered into by Jose Ramon Mas with an unaffiliated party (the "JR 2019 Prepaid Forward Contract," and, as amended to date, the "Prepaid Forward Contract"). The Fourth Amendment amends the Floor Price (as defined below) and Cap Price (as defined below) for each Tranche 2 Component (as defined below), which were determined based on the volume weighted average price (the "VWAP") of MasTec, Inc.'s common stock for a specified period ended on August 11, 2026. The Prepaid Forward Contract provides for the settlement of the transaction, at the option of Jose Ramon Mas, in cash or in Shares. At settlement Jose Ramon Mas will be obligated to deliver to the buyer, on the applicable date in August or September 2027 or 2028 for the applicable component (each, a "Valuation Date") in the first ("Tranche 1") or second ("Tranche 2") tranche, as applicable, of 15 components each ("Tranche 1 Components" or "Tranche 2 Components"), at Jose Ramon Mas's option, up to 100% of the number of Shares pledged for such component or an equivalent amount of cash. Jose Ramon Mas entered into the JR 2019 Prepaid Forward Contract to provide funds for investment in the Miami Major League Soccer franchise. For more information on the terms of the Prepaid Forward Contract, please see Item 6 below.

The purpose of this filing to is report the entry by JM Holdings I on August 10, 2026 into an amendment (the "Fourth Amendment") to the previously reported prepaid variable forward sale contract entered into by JM Holdings I with an unaffiliated party (the "2019 Prepaid Forward Contract," and, as amended to date, the "Prepaid Forward Contract"). The Fourth Amendment amends the Floor Price (as defined below) and Cap Price (as defined below) for each Tranche 1 Component (as defined below), which were determined based on the volume weighted average price (the "VWAP") of MasTec, Inc.'s common stock for a specified period ended on August 11, 2026. The Prepaid Forward Contract provides for the settlement of the transaction, at the option of JM Holdings I, in cash or in Shares. At settlement JM Holdings I will be obligated to deliver to the buyer, on the applicable date in August or September 2027 or 2028 for the applicable component (each, a "Valuation Date") in the first ("Tranche 1") or second ("Tranche 2") tranche, as applicable, of 15 components each ("Tranche 1 Components" or "Tranche 2 Components"), at JM Holdings I's option, up to 100% of the number of Shares pledged for such component or an equivalent amount of cash. JM Holdings I entered into the 2019 Prepaid Forward Contract to provide funds for investment in the Miami Major League Soccer franchise. For more information on the terms of the Prepaid Forward Contract, please see Item 6 below.

The purpose of this filing to is report the entry by JM Holdings I on August 10, 2026 into an amendment (the "Fourth Amendment") to the previously reported prepaid variable forward sale contract entered into by JM Holdings I with an unaffiliated party (the "2019 Prepaid Forward Contract," and, as amended to date, the "Prepaid Forward Contract"). The Fourth Amendment amends the Floor Price (as defined below) and Cap Price (as defined below) for each Tranche 1 Component (as defined below), which were determined based on the volume weighted average price (the "VWAP") of MasTec, Inc.'s common stock for a specified period ended on August 11, 2026. The Prepaid Forward Contract provides for the settlement of the transaction, at the option of JM Holdings I, in cash or in Shares. At settlement JM Holdings I will be obligated to deliver to the buyer, on the applicable date in August or September 2027 or 2028 for the applicable component (each, a "Valuation Date") in the first ("Tranche 1") or second ("Tranche 2") tranche, as applicable, of 15 components each ("Tranche 1 Components" or "Tranche 2 Components"), at JM Holdings I's option, up to 100% of the number of Shares pledged for such component or an equivalent amount of cash. JM Holdings I entered into the 2019 Prepaid Forward Contract to provide funds for investment in the Miami Major League Soccer franchise. For more information on the terms of the Prepaid Forward Contract, please see Item 6 below.

The purpose of this filing to is report entry by Jose Ramon Mas on August 10, 2026 into an amendment (the "Fourth Amendment") to the previously reported prepaid variable forward sale contract entered into by Jose Ramon Mas with an unaffiliated party (the "JR 2019 Prepaid Forward Contract," and, as amended to date, the "Prepaid Forward Contract"). The Fourth Amendment amends the Floor Price (as defined below) and Cap Price (as defined below) for each Tranche 2 Component (as defined below), which were determined based on the volume weighted average price (the "VWAP") of MasTec, Inc.'s common stock for a specified period ended on August 11, 2026. The Prepaid Forward Contract provides for the settlement of the transaction, at the option of Jose Ramon Mas, in cash or in Shares. At settlement Jose Ramon Mas will be obligated to deliver to the buyer, on the applicable date in August or September 2027 or 2028 for the applicable component (each, a "Valuation Date") in the first ("Tranche 1") or second ("Tranche 2") tranche, as applicable, of 15 components each ("Tranche 1 Components" or "Tranche 2 Components"), at Jose Ramon Mas's option, up to 100% of the number of Shares pledged for such component or an equivalent amount of cash. Jose Ramon Mas entered into the JR 2019 Prepaid Forward Contract to provide funds for investment in the Miami Major League Soccer franchise. For more information on the terms of the Prepaid Forward Contract, please see Item 6 below.

The purpose of this filing to is report entry by Jose Ramon Mas on August 10, 2026 into an amendment (the "Fourth Amendment") to the previously reported prepaid variable forward sale contract entered into by Jose Ramon Mas with an unaffiliated party (the "JR 2019 Prepaid Forward Contract," and, as amended to date, the "Prepaid Forward Contract"). The Fourth Amendment amends the Floor Price (as defined below) and Cap Price (as defined below) for each Tranche 2 Component (as defined below), which were determined based on the volume weighted average price (the "VWAP") of MasTec, Inc.'s common stock for a specified period ended on August 11, 2026. The Prepaid Forward Contract provides for the settlement of the transaction, at the option of Jose Ramon Mas, in cash or in Shares. At settlement Jose Ramon Mas will be obligated to deliver to the buyer, on the applicable date in August or September 2027 or 2028 for the applicable component (each, a "Valuation Date") in the first ("Tranche 1") or second ("Tranche 2") tranche, as applicable, of 15 components each ("Tranche 1 Components" or "Tranche 2 Components"), at Jose Ramon Mas's option, up to 100% of the number of Shares pledged for such component or an equivalent amount of cash. Jose Ramon Mas entered into the JR 2019 Prepaid Forward Contract to provide funds for investment in the Miami Major League Soccer franchise. For more information on the terms of the Prepaid Forward Contract, please see Item 6 below.

The purpose of this filing to is report the entry by JM Holdings I on August 10, 2026 into an amendment (the "Fourth Amendment") to the previously reported prepaid variable forward sale contract entered into by JM Holdings I with an unaffiliated party (the "2019 Prepaid Forward Contract," and, as amended to date, the "Prepaid Forward Contract"). The Fourth Amendment amends the Floor Price (as defined below) and Cap Price (as defined below) for each Tranche 1 Component (as defined below), which were determined based on the volume weighted average price (the "VWAP") of MasTec, Inc.'s common stock for a specified period ended on August 11, 2026. The Prepaid Forward Contract provides for the settlement of the transaction, at the option of JM Holdings I, in cash or in Shares. At settlement JM Holdings I will be obligated to deliver to the buyer, on the applicable date in August or September 2027 or 2028 for the applicable component (each, a "Valuation Date") in the first ("Tranche 1") or second ("Tranche 2") tranche, as applicable, of 15 components each ("Tranche 1 Components" or "Tranche 2 Components"), at JM Holdings I's option, up to 100% of the number of Shares pledged for such component or an equivalent amount of cash. JM Holdings I entered into the 2019 Prepaid Forward Contract to provide funds for investment in the Miami Major League Soccer franchise. For more information on the terms of the Prepaid Forward Contract, please see Item 6 below.

The purpose of this filing to is report entry by Jose Ramon Mas on August 10, 2026 into an amendment (the "Fourth Amendment") to the previously reported prepaid variable forward sale contract entered into by Jose Ramon Mas with an unaffiliated party (the "JR 2019 Prepaid Forward Contract," and, as amended to date, the "Prepaid Forward Contract"). The Fourth Amendment amends the Floor Price (as defined below) and Cap Price (as defined below) for each Tranche 2 Component (as defined below), which were determined based on the volume weighted average price (the "VWAP") of MasTec, Inc.'s common stock for a specified period ended on August 11, 2026. The Prepaid Forward Contract provides for the settlement of the transaction, at the option of Jose Ramon Mas, in cash or in Shares. At settlement Jose Ramon Mas will be obligated to deliver to the buyer, on the applicable date in August or September 2027 or 2028 for the applicable component (each, a "Valuation Date") in the first ("Tranche 1") or second ("Tranche 2") tranche, as applicable, of 15 components each ("Tranche 1 Components" or "Tranche 2 Components"), at Jose Ramon Mas's option, up to 100% of the number of Shares pledged for such component or an equivalent amount of cash. Jose Ramon Mas entered into the JR 2019 Prepaid Forward Contract to provide funds for investment in the Miami Major League Soccer franchise. For more information on the terms of the Prepaid Forward Contract, please see Item 6 below.

The purpose of this filing to is report the entry by JM Holdings I on August 10, 2026 into an amendment (the "Fourth Amendment") to the previously reported prepaid variable forward sale contract entered into by JM Holdings I with an unaffiliated party (the "2019 Prepaid Forward Contract," and, as amended to date, the "Prepaid Forward Contract"). The Fourth Amendment amends the Floor Price (as defined below) and Cap Price (as defined below) for each Tranche 1 Component (as defined below), which were determined based on the volume weighted average price (the "VWAP") of MasTec, Inc.'s common stock for a specified period ended on August 11, 2026. The Prepaid Forward Contract provides for the settlement of the transaction, at the option of JM Holdings I, in cash or in Shares. At settlement JM Holdings I will be obligated to deliver to the buyer, on the applicable date in August or September 2027 or 2028 for the applicable component (each, a "Valuation Date") in the first ("Tranche 1") or second ("Tranche 2") tranche, as applicable, of 15 components each ("Tranche 1 Components" or "Tranche 2 Components"), at JM Holdings I's option, up to 100% of the number of Shares pledged for such component or an equivalent amount of cash. JM Holdings I entered into the 2019 Prepaid Forward Contract to provide funds for investment in the Miami Major League Soccer franchise. For more information on the terms of the Prepaid Forward Contract, please see Item 6 below.

The purpose of this filing to is report entry by Jose Ramon Mas on August 10, 2026 into an amendment (the "Fourth Amendment") to the previously reported prepaid variable forward sale contract entered into by Jose Ramon Mas with an unaffiliated party (the "JR 2019 Prepaid Forward Contract," and, as amended to date, the "Prepaid Forward Contract"). The Fourth Amendment amends the Floor Price (as defined below) and Cap Price (as defined below) for each Tranche 2 Component (as defined below), which were determined based on the volume weighted average price (the "VWAP") of MasTec, Inc.'s common stock for a specified period ended on August 11, 2026. The Prepaid Forward Contract provides for the settlement of the transaction, at the option of Jose Ramon Mas, in cash or in Shares. At settlement Jose Ramon Mas will be obligated to deliver to the buyer, on the applicable date in August or September 2027 or 2028 for the applicable component (each, a "Valuation Date") in the first ("Tranche 1") or second ("Tranche 2") tranche, as applicable, of 15 components each ("Tranche 1 Components" or "Tranche 2 Components"), at Jose Ramon Mas's option, up to 100% of the number of Shares pledged for such component or an equivalent amount of cash. Jose Ramon Mas entered into the JR 2019 Prepaid Forward Contract to provide funds for investment in the Miami Major League Soccer franchise. For more information on the terms of the Prepaid Forward Contract, please see Item 6 below.