| In millions, except per share items | Jun-30-23 | Mar-31-23 | Dec-31-22 | Sep-30-22 | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 |
| | 10-Q | 10-Q | 10-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q |
| Net income | -27.3 | -28.2 | -29.2 | -32.2 | -31.2 | -32.9 | -33.9 | -34.9 |
| Depreciation and amortization [+] | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 |
| Depreciation | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 |
| Stock-based compensation | | | -1.3 | -1.4 | | | 0.0 | 2.5 |
| Change in working capital [+] | | | -0.5 | -0.7 | | | 0.0 | -0.2 |
| Other current assets | | | 0.9 | 0.5 | | | 0.0 | 0.3 |
| Accounts payable | | | -0.9 | -1.7 | | | 0.0 | 1.0 |
| Accrued expenses | | | | 0.5 | | | 0.0 | -1.5 |
| Other | | | -0.7 | | | | | |
| Other operating activities | -4.0 | 0.7 | 2.7 | 6.2 | 6.5 | 5.1 | 5.0 | 1.0 |
| Cash from operations | -33.0 | -29.3 | -28.2 | -28.1 | -26.7 | -28.5 | -28.9 | -31.6 |
| |
| Capital expenditures | 0.3 | 0.2 | 0.2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| Purchases of property and equipment | 0.3 | 0.2 | 0.2 | 0.0 | | | | |
| Purchases of short-term investments, net | 229.1 | 263.6 | 236.7 | 49.4 | 54.2 | | | |
| Purchases of short-term investments | | 243.6 | 234.6 | 47.4 | 54.2 | | | |
| Sales of short-term investments | 39.7 | 20.0 | | 2.0 | | | | |
| Other cash from investing | -253.9 | -362.3 | -344.2 | | -108.4 | | | |
| Cash from investing | -24.6 | -98.4 | -107.4 | -59.1 | -54.2 | 0.0 | 0.0 | 0.0 |
| |
| Repurchase of common stock, net | | | -51.8 | 51.2 | | | | |
| Option exercises | 0.2 | 0.2 | | 0.2 | 0.0 | | 0.0 | |
| Financing costs | | | 0.0 | | | | 0.0 | -0.1 |
| Other cash from financing | 98.6 | 162.3 | 163.3 | 73.4 | 69.3 | 16.0 | 20.8 | 7.6 |
| Cash from financing | 46.6 | 110.2 | 111.3 | 124.4 | 69.2 | 16.0 | 20.8 | 7.7 |
| |
| Free cash flow | -32.7 | -29.1 | -28.0 | -28.1 | -26.7 | -28.5 | -28.9 | -31.6 |
| Per share (diluted) | ($0.40) | ($0.40) | ($0.50) | ($0.62) | ($0.79) | ($1.19) | ($1.38) | ($1.60) |
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