| Clark & Co. | L. J. | Glenburnie, West Wagin | 8LC and 71B, 10A | 1962 |
| Clark & Phillips | - | Springfield Estate, Northam | 7CL | 1924 |
| Clark & Power | - | Midga Station, Onslow | 0PQ | 1962 |
| Clark & Son | E. | Wendowie, Serpentine | CV9 and 46D, 18E | 1962 |
| Clark & Son | J. P. | Pullagaroo Station, Payne's Find | EO6 and 54F, 17D | 1962 |
| Clark & Son | W. T. | Culcurring, Moulyinning | 9OC and 11B, 12E | 1962 |
| Clark & Sons | - | Meadow Station, Geraldton | CK9 and 30B, 18E | 1962 |
| Clark & Sons | J. & H. P. | Ellangowen, Babakin | C8B and 48B, 49A | 1962 |
| Clark & Sons | W. J. | Tachbrook, Bokal, via Wagin | D0W and 38D, 107E | 1962 |
| Clark & Stock | - | Belka | KZ9 | 1924 |
| Clark Bros. | - | Bannister River, Wandering | C2H | 1912 |
| Clark Bros. | - | Bannister River, Wandering | C2H | 1924 |
| Clark Bros. | - | Avondale, Dumbleyung | B8G and 10B, 11E | 1962 |
| Clark Bros. & Roberts | - | Pullagaroo, Paynes' Find, via Yalgoo | EO6 | 1924 |
| Clarke | A. F. | Highlands, Woolgenillup, Mt. Barker | CK9 and 48B, 13E | 1962 |
| Clarke | A. G. | Northandene, Wongan Hills | 5EX and 6B, 43A | 1962 |
| Clarke | A. J. | Koolkarnin, Wongan Hills | 3CA | 1924 |
| Clarke | A. R. & S. L. | Ptn. Avon R. & Q., Northam | 1AC and 114A, 35B | 1962 |
| Clarke | A. W. | Wms. Locs. 7566, 8409, 11115, Moulyinning | WC5 and 6B, 23E | 1962 |
| Clarke | B. B. & E. | 20157, Wongan Hills | CE1 and 109B, 71A | 1962 |
| Clarke | B. R. & D. E. | Serenity, Burakin | 4BC and 118E, 16D | 1962 |
| Clarke | B. W. J. | Ningham Loc. 1845, 676, 305, 675, 1817, 306, Wongan Hills | 9KC and 110A, 20B | 1962 |
| Clarke | C. I. | Ardmona Farm, Wyening | 1XC and 102B, 57F | 1962 |
| Clarke | C. J. | White Gully, Bolgart | LK0 and 17B, 36D | 1962 |
| Clarke | Charles Henry | Roe Loc. 85, Newdegate, Lake Grace | 2ZQ | 1925 |
| Clarke | D. S. | Peel Est. Lots 134, 391, 820, Serpentine | 5VC and 105A, 30B | 1962 |
| Clarke | E. G. | Harrington, Mt. Barker | G3C and 12C, 67E | 1962 |
| Clarke | E. J. | Nelson Loc. 10193, Walpole | Y6J | 1962 |
| Clarke | E. J. & W. | 10781-4, 13810, 12319, Kukerin | EC4 and 21B, 6A | 1962 |
| Clarke | E. M. | Orange Grove, Roelands | EC8 | 1912 |
| Clarke | E. M. | Orange Grove, Roelands | EC8 | 1924 |
| Clarke | E. M. | Loc. 2873, Yelverton | VC8 | 1962 |
| Clarke | Edward B. | Rupertswood, Moulyinning | YC8 | 1924 |
| Clarke | Emmie | Brunswick Junction | 3NE | 1924 |
| Clarke | Ernest Sam. | Normanhurst, Wadana, Mullewa | YC4 | 1924 |
| Clarke | Est of E. B. | Rupertswood, Moulyinning | YC8 and 11B, 34E | 1962 |
| Clarke | Eweu | Water Vale Farm, North Wandering Road, via Pingelly | U4C | 1924 |
| Clarke | F. N. & M. A. | Avon Loc. 15813, Quairading | 7FC and 50C, 109E | 1962 |
| Clarke | Fredk | Brooklyn, Bridgetown | C1C | 1924 |
| Clarke | Fredk. | Brooklyn, Bridgetown, | C1C | 1912 |
| Clarke | G. D. | Commonage, Moora | 1GC | 1912 |
| Clarke | G. D. | Commonage, Moora | 1GC | 1924 |
| Clarke | Grace E. | Location 11108, Elabbin, via Merriden | Z1G | 1912 |
| Clarke | Grace E. | Loc.11108, Ellabbin | Z1G | 1924 |
| Clarke | H. E. | Warraling, Nangeenan | A1C | 1912 |
| Clarke | H. E. | Warraling, Nangeenan | A1C | 1924 |
| Clarke | H. F. | Pepper Grove, Armadale | 0KF | 1924 |
| Clarke | H. W. | Northdale, Minnivale | LM9 and 21C, 49E | 1962 |
| Clarke | J. A. | Belmont Avenue, Belmont | O5K | 1924 |
| Clarke | J. A. | 394/1439, Balfour Downs Station, via Meekatharra | CJ5 and 13C, 49E | 1962 |
