EXHIBIT 99.1
JOINT FILING AGREEMENT
In accordance with Rule 13d-1(k)(1) promulgated under the Securities Exchange Act of 1934, as amended, the undersigned hereby agree to the joint filing with each of the Reporting Persons (as such term is defined in the Schedule 13G referred to below) on behalf of each of them of a statement on Schedule 13G (including amendments thereto) with respect to the Class A common stock, par value $0.0001 per share, of X-Energy, Inc., and that this agreement may be included as an exhibit to such joint filing.
Dated: August 12, 2026
| Ares Partners Holdco LLC | ||
| /s/ Anton Feingold | ||
| Name: | Anton Feingold | |
| Title: | Authorized Signatory | |
| Ares X-Energy Holdings LP | ||
| /s/ Anton Feingold | ||
| Name: | Anton Feingold | |
| Title: | Authorized Signatory | |
| Ares X-Energy Co-Invest LP | ||
| /s/ Matthew Jill | ||
| Name: | Matthew Jill | |
| Title: | Authorized Signatory | |
| ACIP Investments Pooling LLC - Series 31 | ||
| /s/ Noah Ehrenpreis | ||
| Name: | Noah Ehrenpreis | |
| Title: | Authorized Signatory | |