SUBSTITUTE POWER OF ATTORNEY


I, Mark J. Casey, the undersigned, by a Power of Attorney dated
April 14, 2014 (the "POA"), was appointed to act as the true
and lawful attorney-in-fact for and on behalf of Claus Egstrand
in his capacity as the Senior Vice President and General Manager,
International (the "Executive Officer") of Hologic, Inc. (the
"Company") to do and perform any and all acts for and on behalf
of the Executive Officer which may be necessary or desirable to
complete and execute any Forms 3, 4, or 5, complete and execute any
amendment(s) thereto, and timely file such form(s) with the United
States Securities and Exchange Commission and any stock exchange or
similar authority.

As authorized in the POA, I hereby delegate all of the powers contained
therein to each of Robert W. McMahon, Anne M. Liddy and Alisha
Hankins, individually and signing singly, to act as the Executive
Officers?s true and lawful substitute attorney-in-fact.

Further, the undersigned hereby ratifies all acts, deeds and things,
which any substitute attorney-in-fact will lawfully do and execute in
pursuance of the powers granted herein.

This Substitute Power of Attorney shall remain in full force and effect
until revoked by the undersigned, the POA is revoked or the Executive
Officer is no longer required to file Forms 3, 4, and 5 with respect
to the Executive Officer's holdings of and transactions in securities
issued by the Company.

IN WITNESS WHEREOF, the undersigned has caused this Substitute Power
of Attorney to be executed as of this 15th day of December, 2014.




/s/Mark J. Casey
Attorney-in-fact