EXHIBIT I

JOINT ACQUISITION STATEMENT PURSUANT TO RULE 13d-1(k)

The undersigned acknowledge and agree that the foregoing statement on Schedule 13G is filed on behalf of each of the undersigned and that all subsequent amendments to this statement on Schedule 13G shall be filed on behalf of each of the undersigned without the necessity of filing additional joint acquisition statements. The undersigned acknowledge that each shall be responsible for the timely filing of such amendments, and for the completeness and accuracy of the information concerning him or it contained therein, but shall not be responsible for the completeness and accuracy of the information concerning the others, except to the extent that he or it knows or has reason to believe that such information is inaccurate.

Dated:

February 14, 2018

	HEALTHCOR MANAGEMENT, L.P.

		By: HealthCor Associates, LLC, its general partner

		/s/ Anabelle P. Gray
		Name: Anabelle P. Gray
		Title: General Counsel

	HEALTHCOR OFFSHORE GP, LLC, for itself and as general partner of behalf of HEALTHCOR OFFSHORE MASTER FUND, L.P.

		By: HealthCor Group, LLC, its general partner

		/s/ Anabelle P. Gray
		Name: Anabelle P. Gray
		Title: General Counsel

	HEALTHCOR OFFSHORE II GP, LLC, for itself and as general partner of behalf of HEALTHCOR SANATATE OFFSHORE MASTER FUND, L.P.

		By: HealthCor Group, LLC, its general partner

		/s/ Anabelle P. Gray
		Name: Anabelle P. Gray
		Title: General Counsel

	HEALTHCOR OFFSHORE III GP, LLC, for itself and as general partner of behalf of HEALTHCOR CO-INVEST SANATATE MASTER FUND, L.P.

		By: HealthCor Group, LLC, its general partner

		/s/ Anabelle P. Gray
		Name: Anabelle P. Gray
		Title: General Counsel

	HEALTHCOR ASSOCIATES, LLC

		/s/ Anabelle P. Gray
		Name: Anabelle P. Gray
		Title: General Counsel

	HEALTHCOR GROUP, LLC

		/s/ Anabelle P. Gray
		Name: Anabelle P. Gray
		Title: General Counsel

	JOSEPH HEALEY, Individually

		/s/ Joseph Healey

	ARTHUR COHEN, Individually

		/s/ Arthur Cohen

Bioverativ Inc. SC 13G/A