Item 1
1(a) Name of Issuer: Generation Bio Co.
1(b) Address of Issuer’s Principal Executive Offices:
301 Binney Street, Cambridge, MA 02142, United States
Item 2
2(a) Name of Person Filing: BB Biotech AG (“BB Biotech”) on behalf of its wholly-owned subsidiary, Biotech Growth N.V. (“Biotech Growth”)
2(b) Address of Principal Business Office or, if none, Residence:
BB Biotech: Schwertstrasse 6, CH-8200 Schaffhausen, Switzerland
Biotech Growth: Ara Hill Top Building, Unit A-5, Pletterijweg Oost 1, Curaçao
2(c) Citizenship: BB Biotech AG: Switzerland
Biotech Growth N.V.: Curaçao
2(d) Title of Class of Securities: Common Stock, $0.0001 par value
2(e) CUSIP Number: 37148K100
Item 4. Ownership
Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.
(a) Amount beneficially owned: 3,310,869
(b) Percent of class: 5.0%
(c) Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote 0
(ii) Shared power to vote or to direct the vote 3,310,869
(iii) Sole power to dispose or to direct the disposition of 0
(iv) Shared power to dispose or to direct the disposition of 3,310,869
Item 5. Ownership of Five Percent or Less of a Class
If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following: ☒
Item 7. Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person.
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