| amyx, inc. E27664402022-8 | Foreign Corporation | Active In good standing | Treasurer | 3475 E. Foothill Blvd., Pasadena CA 91101 | 2022 |
| ard of vermont, inc. E34265712023-0 | Foreign Corporation | Active In good standing | Treasurer | 3475 E. Foothill Blvd., Pasadena CA 91101 | 2023 |
| cosentini associates, inc. E0023902006-5 | Foreign Corporation | Active In good standing | Treasurer | 3475 E. Foothill Blvd., Pasadena CA 91101 | 2006 |
| glumac E0066372007-2 | Foreign Corporation | Active In good standing | Treasurer | 3475 E. Foothill Blvd., Pasadena CA 91101 | 2007 |
| management systems international of dc, inc. E28017542022-1 | Foreign Corporation | Active In good standing | Treasurer | 3475 E Foothill Blvd., Pasadena CA 91101 | 2022 |
| piteau associates usa ltd. E0215072013-5 | Domestic Corporation | Active In good standing | Treasurer | 3475 E. Foothill Blvd., Pasadena CA 91101 | 2013 |
| tetra tech bas, inc. E0049872010-6 | Foreign Corporation | Active In good standing | Treasurer | 3475 E. Foothill Blvd., Pasadena CA 91101 | 2010 |
| tetra tech ec, inc. C3715-2003 | Foreign Corporation | Active In good standing | Treasurer | 3475 E FOOTHILL BLVD, PASADENA CA 91107 | 2003 |
| tetra tech es, inc. E0265262019-4 | Foreign Corporation | Active In good standing | Treasurer | 3475 E FOOTHILL BLVD, PASADENA CA 91107 | 2019 |
| tetra tech executive services, inc. E17412452021-1 | Foreign Corporation | Active In good standing | Treasurer | 3475 E. Foothill Blvd., Pasadena CA 91101 | 2021 |
| tetra tech technical services, inc. C9874-1999 | Foreign Corporation | Active In good standing | Treasurer | 3475 E. Foothill Blvd., Pasadena CA 91101 | 1999 |
| tetra tech, inc. C11134-1992 | Foreign Corporation | Active In good standing | Treasurer | 3475 E. Foothill Blvd, Pasadena CA 91101 | 1992 |
| bas construction co. of california E0189622010-6 | Foreign Corporation | Merged Not in good standing | Treasurer | 3475 E FOOTHILL BLVD, PASADENA CA 91107 | 2010 |
| GEOTRANS, INC. C22246-1997 | Foreign Corporation | Merged Not in good standing | Treasurer | 3475 E FOOTHILL BLVD, PASADENA CA 91107 | 1997 |
| tetra tech construction, inc. E0555542009-7 | Foreign Corporation | Withdrawn Not in good standing | Treasurer | 3475 E FOOTHILL BLVD, PASADENA CA 91107 | 2009 |
| tetra tech em, inc. C28340-1998 | Foreign Corporation | Merged Not in good standing | Treasurer | 3475 EAST FOOTHILL BLVD, PASADENA CA 91107 | 1998 |
| tetra tech emc, inc. E0429732016-6 | Foreign Corporation | Withdrawn Not in good standing | Treasurer | 3475 E FOOTHILL BLVD, PASADENA CA 91107 | 2016 |
| tetra tech ma, inc. E0218802016-0 | Foreign Corporation | Withdrawn Not in good standing | Treasurer | 3475 E FOOTHILL BLVD, PASADENA CA 91107 | 2016 |