Since 2005, Freeport-McMoRan has sought independent verification of its annual sustainability reports. External assurance of our 2017 WTSD reporting was conducted by Corporate Integrity Ltd. in accordance with the International Council on Mining & Metals (ICMM) Sustainable Development Framework Assurance Procedure. Since 2009, site-level external assurance has been completed multiple times at all active mining operations. We are conducting site-level external assurance at operations at a minimum of once every three years, with annual assurance engagements at PTFI and Cerro Verde. The 2017 Assurance Statement can be found here.

External Assurance Reviews Since 2009
Operation Name Number Operation Name Number

Atlantic Copper

2

Miami

3

Bagdad

4

Morenci

4

Cerro Verde

6

Phoenix Corporate Office

9

Chino

3

PT Freeport Indonesia

7
Climax Mine 2 Rotterdam 2

El Abra

4

Safford

3

El Paso

5

Sierrita

3

Fort Madison

2

Stowmarket

2

Henderson

3 Tyrone 3
Kokkola 3