X0306 4 2021-11-17 0 0001801368 MP Materials Corp. / DE MP 0001831686 Corbett Ryan 6720 VIA AUSTI PARKWAY, SUITE 450 LAS VEGAS NV 89119 0 1 0 0 Chief Financial Officer Common Stock 2021-11-17 4 F 0 20249 44.62 D 230905 D Common Stock 2021-11-18 4 S 0 24066 43.06 D 206839 D Common Stock 2021-11-18 4 S 0 13085 43.54 D 193754 D Common Stock 2021-11-18 4 S 0 2600 44.60 D 191154 D The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 28, 2021. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $42.37 to $43.36, inclusive. The reporting person undertakes to provide to MP Materials Corp., any security holder of MP Materials Corp., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in footnote (2) to this Form 4. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $43.37 to $44.22, inclusive. The reporting person undertakes to provide to MP Materials Corp., any security holder of MP Materials Corp., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in footnote (3) to this Form 4. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $44.38 to $44.84, inclusive. The reporting person undertakes to provide to MP Materials Corp., any security holder of MP Materials Corp., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in footnote (4) to this Form 4. /s/ Elliot D. Hoops, Attorney-In-Fact for Ryan Corbett 2021-11-19