REGN

SEC source: 0001708138-17-000002 · edgardoc.xml · nonDerivative · entry 8

STAHL NEIL · CIK 0001226689 · EVP Research and Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 26,562

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001708138-17-000002 · edgardoc.xml · nonDerivative · entry 7

STAHL NEIL · CIK 0001226689 · EVP Research and Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 26,662

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 15

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,641,744

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F18 · price: Purchase prices range from $483.57 to $484.50 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 14

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,637,036

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F17 · price: Purchase prices range from $482.57 to $483.50 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 13

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,618,725

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F16 · price: Purchase prices range from $481.57 to $482.56 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 12

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,595,235

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F15 · price: Purchase prices range from $480.54 to $481.53 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 11

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,580,038

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F14 · price: Purchase prices range from $479.54 to $480.51 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 10

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,567,328

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F13 · price: Purchase prices range from $478.53 to $479.48 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 9

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,560,821

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F12 · price: Purchase prices range from $475.70 to $476.47 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 8

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,554,509

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F11 · price: Purchase prices range from $474.50 to $475.49 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 7

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,542,489

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F10 · price: Purchase prices range from $473.45 to $474.10 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 6

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,535,421

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F9 · price: Purchase prices range from $472.45 to $473.33 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 5

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,529,615

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F8 · price: Purchase prices range from $471.43 to $472.25 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 4

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,522,172

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F7 · price: Purchase prices range from $470.31 to $470.99 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 3

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,508,628

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F6 · price: Purchase prices range from $469.19 to $470.04 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 2

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,506,496

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F5 · price: Purchase prices range from $468.01 to $468.29 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-023988 · form4.xml · nonDerivative · entry 1

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,506,096

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F3 · price: Purchase prices range from $465.88 to $466.56 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,842,192 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001708138-17-000002 · edgardoc.xml · derivative · entry 23

STAHL NEIL · CIK 0001226689 · EVP Research and Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 4,527 shares

Expires 2017-12-17

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001708138-17-000002 · edgardoc.xml · derivative · entry 22

STAHL NEIL · CIK 0001226689 · EVP Research and Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 6,017 shares

Expires 2017-12-17

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001708138-17-000002 · edgardoc.xml · nonDerivative · entry 6

STAHL NEIL · CIK 0001226689 · EVP Research and Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 26,762

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001708138-17-000002 · edgardoc.xml · nonDerivative · entry 5

STAHL NEIL · CIK 0001226689 · EVP Research and Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 28,929

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001708138-17-000002 · edgardoc.xml · nonDerivative · entry 4

STAHL NEIL · CIK 0001226689 · EVP Research and Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 30,814

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001708138-17-000002 · edgardoc.xml · nonDerivative · entry 3

STAHL NEIL · CIK 0001226689 · EVP Research and Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 24,797

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001708138-17-000002 · edgardoc.xml · nonDerivative · entry 2

STAHL NEIL · CIK 0001226689 · EVP Research and Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 25,865

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001708138-17-000002 · edgardoc.xml · nonDerivative · entry 1

STAHL NEIL · CIK 0001226689 · EVP Research and Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 28,477

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001237899-17-000017 · edgardoc.xml · nonDerivative · entry 5

VAGELOS P ROY · CIK 0001013064 · Director · Chairman of the Board

10b5-1 filing: Not disclosed

Ownership: Indirect · by Spouse as Trustee

Disclosed balance after: 83,652

F3 · price: Represents volume-weighted average price of sales of 800 shares of Company stock on May 25, 2017 at prices ranging from $459.01 to $459.53. Upon request by the Commission staff, the Company, or a security holder of the Company, the reporting person will provide full information regarding the number of shares sold by the reporting person on May 25, 2017 at each separate price.

SEC source: 0001237899-17-000017 · edgardoc.xml · nonDerivative · entry 4

VAGELOS P ROY · CIK 0001013064 · Director · Chairman of the Board

10b5-1 filing: Not disclosed

Ownership: Indirect · by Spouse as Trustee

Disclosed balance after: 84,452

F2 · price: Represents volume-weighted average price of sales of 4,985 shares of Company stock on May 25, 2017 at prices ranging from $458.00 to $458.98. Upon request by the Commission staff, the Company, or a security holder of the Company, the reporting person will provide full information regarding the number of shares sold by the reporting person on May 25, 2017 at each separate price.

SEC source: 0001237899-17-000017 · edgardoc.xml · nonDerivative · entry 3

VAGELOS P ROY · CIK 0001013064 · Director · Chairman of the Board

10b5-1 filing: Not disclosed

Ownership: Indirect · by Spouse as Trustee

Disclosed balance after: 89,437

F1 · price: Represents volume-weighted average price of sales of 3,510 shares of Company stock on May 25, 2017 at prices ranging from $457.05 to $457.99. Upon request by the Commission staff, the Company, or a security holder of the Company, the reporting person will provide full information regarding the number of shares sold by the reporting person on May 25, 2017 at each separate price.

SEC source: 0001237899-17-000016 · edgardoc.xml · derivative · entry 4

BROWN MICHAEL S · CIK 0001174475 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,000

Underlying: Common Stock · 3,000 shares

Expires 2023-01-02

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

F2 · derivative.exercise_date: The stock option becomes exercisable in three equal annual installments, commencing one year after the date of grant.

SEC source: 0001237899-17-000016 · edgardoc.xml · nonDerivative · entry 2

BROWN MICHAEL S · CIK 0001174475 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001237899-17-000016 · edgardoc.xml · nonDerivative · entry 1

BROWN MICHAEL S · CIK 0001174475 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,000

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001237899-18-000008 · edgardoc.xml · nonDerivative · entry 2

RYAN ARTHUR F · CIK 0001187443 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 32,000

SEC source: 0001237899-18-000008 · edgardoc.xml · nonDerivative · entry 1

RYAN ARTHUR F · CIK 0001187443 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 33,000

SEC source: 0001237899-17-000017 · edgardoc.xml · nonDerivative · entry 2

VAGELOS P ROY · CIK 0001013064 · Director · Chairman of the Board

10b5-1 filing: Not disclosed

Ownership: Indirect · by CLAT

Disclosed balance after: 150,707

SEC source: 0001237899-17-000015 · edgardoc.xml · derivative · entry 4

BROWN MICHAEL S · CIK 0001174475 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 11,000

Underlying: Common Stock · 1,000 shares

Expires 2023-01-02

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

F2 · derivative.exercise_date: The stock option becomes exercisable in three equal annual installments, commencing one year after the date of grant.

SEC source: 0001237899-17-000015 · edgardoc.xml · nonDerivative · entry 2

BROWN MICHAEL S · CIK 0001174475 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001237899-17-000015 · edgardoc.xml · nonDerivative · entry 1

BROWN MICHAEL S · CIK 0001174475 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,000

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: Disposition/acquisition made pursuant to a plan intended to comply with Rule 10b5-1(c).

SEC source: 0001104659-17-005427 · a4.xml · derivative · entry 1

COLES N ANTHONY · CIK 0001197018 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 13,050

Underlying: Common Stock · 13,050 shares

Expires 2027-01-27

F1 · derivative.exercise_date: The stock option becomes exercisable in three equal annual installments, commencing one year after the date of grant.

SEC source: 0001140361-17-001832 · form4.xml · nonDerivative · entry 18

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,505,694

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F21 · price: Purchase prices range from $379.38 to $379.80 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,706,142 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-001832 · form4.xml · nonDerivative · entry 17

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,503,584

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F20 · price: Purchase prices range from $378.37 to $379.36 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,706,142 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-001832 · form4.xml · nonDerivative · entry 16

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,494,064

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F19 · price: Purchase prices range from $377.36 to $378.35 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,706,142 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-001832 · form4.xml · nonDerivative · entry 15

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,488,751

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F18 · price: Purchase prices range from $376.36 to $377.34 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,706,142 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-001832 · form4.xml · nonDerivative · entry 14

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,484,900

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F17 · price: Purchase prices range from $375.36 to $376.34 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,706,142 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-001832 · form4.xml · nonDerivative · entry 13

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,481,884

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F16 · price: Purchase prices range from $374.31 to $375.24 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,706,142 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-001832 · form4.xml · nonDerivative · entry 12

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,478,054

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F15 · price: Purchase prices range from $373.30 to $374.28 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,706,142 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-001832 · form4.xml · nonDerivative · entry 11

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,475,270

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F14 · price: Purchase prices range from $372.29 to $373.27 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,706,142 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-001832 · form4.xml · nonDerivative · entry 10

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,472,595

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F13 · price: Purchase prices range from $371.05 to $372.02 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,706,142 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-001832 · form4.xml · nonDerivative · entry 9

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,471,336

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F12 · price: Purchase prices range from $369.87 to $370.59 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,706,142 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-001832 · form4.xml · nonDerivative · entry 8

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,470,436

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F11 · price: Purchase prices range from $368.84 to $369.79 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,706,142 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.

SEC source: 0001140361-17-001832 · form4.xml · nonDerivative · entry 7

Sanofi · CIK 0001121404 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See note

Disclosed balance after: 23,467,919

F1 · shares: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F2 · shares: Represents shares acquired directly by sanofi-aventis Amerique du Nord ("SAAN").

F1 · price: The number of securities reported represents an aggregate number of shares purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. The Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares purchased by the Reporting Person at each separate price within the range.

F10 · price: Purchase prices range from $367.84 to $368.78 per share, inclusive.

F4 · ownership.nature: Indirectly owned through (a) SAAN, a direct, wholly-owned subsidiary of Sanofi, and (b) Aventis Pharmaceuticals Inc. ("Aventis"), an indirect, wholly-owned subsidiary of SAAN. After giving effect to all acquisitions reported on this Form 4, the number of shares beneficially owned directly by SAAN and Aventis was 20,706,142 shares and 2,799,552 shares, respectively. Pursuant to the Amended and Restated Investor Agreement, dated as of January 11, 2014, by and among Sanofi, SAAN, sanofi-aventis US LLC, Aventis (collectively, the "Sanofi Parties") and the Issuer, the Sanofi Parties have agreed to vote their respective shares of the Issuer, subject to specified exceptions, in accordance with the recommendation of the Issuer's Board of Directors.