Item 1
1(a) Name of Issuer: Tesaro, Inc.
1(b) Address of Issuer’s Principal Executive Offices:
| | 1000 Winter Street, Waltham, Massachusetts 02451 |
Item 2
2(a) Name of Person Filing:BB Biotech AG (“BB Biotech”) on behalf of its wholly-owned subsidiary, Biotech Target N.V. (“Biotech Target”)
| 2(b) | Address of Principal Business Office or, if none, Residence: |
| BB | Biotech AG: Schwertstrasse 6,CH-8200 Schaffhausen, Switzerland |
| Biotech | Target N.V.: Snipweg 26, Curacao |
| 2(c) | Citizenship:BB Biotech AG: Switzerland |
Biotech Target N.V.: Curacao
2(d) Title of Class of Securities Common Stock, $0.0001 par value
2(e) CUSIP Number 881569107
Item 3
If this statement is filed pursuant to Rule13d-1(b), or13d-2(b) or (c), check whether the person filing is a:
a. [ ] Broker or Dealer registered under Section 15 of the Act.
b. [ ] Bank as defined in Section 3(a)(6) of the Act.
c. [ ] Insurance company as defined in Section 3(a)(19) of the Act.
d. [ ] Investment company registered under section 8 of the Investment Company Act of 1940.
e. [ ] An investment adviser in accordance with Rule13d-1(b)(1)(ii)(E);
f. [ ] An employee benefit plan or endowment fund in accordance with Rule13d-1(b)(1)(ii)(F);
g. [ ] A parent holding company or control person in accordance with Rule13d-1(b)(1)(ii)(G);
h. [ ] A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
i. [ ] A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940;
j. [ ] Group, in accordance with Rule13d-1(b)(1)(ii)(J).
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