| Expenses by nature |
6Expenses by nature Included within administrative expenses and research and development expenses are the following expenses. | | | | | | | | | 2024 | | 2023 | | 2022 | | | £ 000 | | £ 000 | | £ 000 | Research and development staff costs (excluding share-based payment expenses) | | 27,148 | | 23,830 | | 17,580 | Research and development consultancy | | 12,179 | | 16,193 | | 18,004 | Research and development components, parts and tooling | | 20,561 | | 25,350 | | 13,545 | Total research and development expenses | | 59,888 | | 65,373 | | 49,129 | Administrative staff costs (excluding share-based payment expenses) | | 9,682 | | 9,616 | | 8,014 | Share based payment expenses (note 22) | | 7,486 | | 8,816 | | 23,189 | Consultancy costs | | 2,961 | | 1,914 | | 2,479 | Legal and financial advisory costs | | 4,609 | | 2,296 | | 2,949 | HR advisory and recruitment costs | | 650 | | 968 | | 2,089 | IT hardware and software costs | | 7,192 | | 6,314 | | 4,348 | Insurance expenses | | 1,357 | | 2,110 | | 2,698 | Marketing costs | | 1,761 | | 688 | | 1,728 | Premises expenses | | 2,183 | | 1,870 | | 1,614 | Depreciation expense | | 1,088 | | 892 | | 577 | Amortization expense | | 885 | | 1,164 | | 1,195 | Depreciation on right of use property assets | | 730 | | 658 | | 411 | Goodwill impairment | | — | | — | | 1,473 | Other administrative expenses | | 2,827 | | 3,512 | | 2,042 | Total administrative expenses | | 43,411 | | 40,818 | | 54,806 | Related party administrative expenses | | 1,280 | | 83 | | 83 | Total administrative & research and development expenses | | 104,579 | | 106,274 | | 104,018 |
Staff costs relate primarily to salary and salary - related expenses, including social security and pension contributions. Staff costs exclude share-based payments – see note 22 for further details. Share-based payment expense primary relates to both R&D staff and administrative staff and includes the following: | | | | | | | | | 2024 | | 2023 | | 2022 | | | £ 000 | | £ 000 | | £ 000 | 2021 Incentive Plan | | 7,142 | | 8,084 | | 14,512 | Enterprise Management Incentive | | 344 | | 732 | | 7,858 | Issuance of shares to suppliers and partners | | — | | — | | 819 | | | 7,486 | | 8,816 | | 23,189 |
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