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SUBSEQUENT EVENTS | 3 Months Ended
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Mar. 31, 2020
Subsequent Events [Abstract] |
SUBSEQUENT EVENTS | SUBSEQUENT EVENTSIn April 2020, the collaboration and license agreement with Biogen became effective following termination of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, and satisfaction of other closing conditions, including the payment of $225.0 million for the purchase of the Biogen Shares. Under the collaboration and license agreement, Biogen paid the Company an upfront license fee of $125.0 million in May 2020.

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- Definition The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 855 -URI http://asc.fasb.org/topic&trid=2122774 + Details
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