Bioverativ Inc. (BIVV) Is Too Rich For My Blood But Activist Jeff Ubben Likes It

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Page 11 of 11 – SEC Filing
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CUSIP NO. 09075E100 Page 11 of 12
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ValueAct Holdings, L.P., by
ValueAct Holdings GP, LLC, its
General Partner

By: /s/ Bradley E. Singer
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Dated: March 2, 2017 Bradley E. Singer, Chief Operating Officer

ValueAct Holdings GP, LLC

By: /s/ Bradley E. Singer
————————————–
Dated: March 2, 2017 Bradley E. Singer, Chief Operating Officer

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CUSIP NO. 09075E100 Page 12 of 12
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Exhibit 1

JOINT FILING UNDERTAKING

The undersigned parties hereby agree that the Schedule 13D filed herewith
(and any amendments thereto) relating to the Common Stock of Bioverativ Inc.,
is being filed jointly on behalf of each of them with the Securities and
Exchange Commission pursuant to Section 13(d) of the Securities Exchange Act
of 1934, as amended.

ValueAct Capital Master Fund L.P., by
VA Partners I, LLC, its General Partner

By: /s/ Bradley E. Singer
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Dated: March 2, 2017 Bradley E. Singer, Chief Operating Officer

VA Partners I, LLC

By: /s/ Bradley E. Singer
————————————–
Dated: March 2, 2017 Bradley E. Singer, Chief Operating Officer

ValueAct Capital Management, L.P., by
ValueAct Capital Management, LLC its
General Partner

By: /s/ Bradley E. Singer
————————————–
Dated: March 2, 2017 Bradley E. Singer, Chief Operating Officer

ValueAct Capital Management, LLC

By: /s/ Bradley E. Singer
————————————–
Dated: March 2, 2017 Bradley E. Singer, Chief Operating Officer

ValueAct Holdings, L.P., by
ValueAct Holdings GP, LLC, its
General Partner

By: /s/ Bradley E. Singer
————————————–
Dated: March 2, 2017 Bradley E. Singer, Chief Operating Officer

ValueAct Holdings GP, LLC

By: /s/ Bradley E. Singer
————————————–
Dated: March 2, 2017 Bradley E. Singer, Chief Operating Officer

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