| Assets | — | — |
| Current assets | — | — |
| Cash and cash equivalents | 2,375a | 1,049.9a |
| Accounts receivable, net | 1,404.8a | 1,664.1a |
| Due from anti-CD20 therapeutic programs | 464a | 435.9a |
| Inventory | 2,460.5a | 2,527.4a |
| Other current assets | 752.5a | 1,182a |
| Total current assets | 7,456.8a | 6,859.3a |
| Property, plant and equipment, net | 3,181.3a | 3,309.7a |
| Operating lease assets | 356.4a | 420a |
| Intangible assets, net | 9,691.2a | 8,363a |
| Goodwill | 6,478.9a | 6,219.2a |
| Deferred tax asset | 324.2a | 928.6a |
| Investments and other assets | 560.5a | 745a |
| Total assets | 28,049.3a | 26,844.8a |
| Liabilities and equity | — | — |
| Current liabilities | — | — |
| Current portion of notes payable and term loan | 1,748.6a | 150a |
| Taxes payable | 548.3a | 257.4a |
| Accounts payable | 424.2a | 403.3a |
| Accrued expense and other | 2,807.7a | 2,623.6a |
| Total current liabilities | 5,528.8a | 3,434.3a |
| Notes payable and term loan | 4,547.2a | 6,788.2a |
| Deferred tax liability | 190.5a | 641.8a |
| Long-term operating lease liabilities | 334.5a | 400a |
| Other long-term liabilities | 732.3a | 781.1a |
| Total liabilities | 11,333.3a | 12,045.4a |
| Equity: Biogen Inc. shareholders’ equity | — | — |
| Preferred stock | 0a | 0a |
| Common stock | 0.1a | 0.1a |
| Additional paid-in capital | 569.4a | 302.5a |
| Accumulated other comprehensive income (loss) | -136.2a | -153.7a |
| Retained earnings | 19,259.8a | 17,627.6a |
| Treasury stock, at cost | -2,977.1a | -2,977.1a |
| Total equity | 16,716a | 14,799.4a |
| Total liabilities and equity | 28,049.3a | 26,844.8a |