13G Filing: North Tide Capital Master, LP and Select Medical Holdings Corp (SEM)

Item 1.

(a)

Name of Issuer

Select Medical Holdings Corporation

(b)

Address of Issuer’s Principal Executive Offices

4714 Gettysburg Road, P.O. Box 2034, Mechanicsburg, Pennsylvania 17055

Item 2.

(a)

Name of Person Filing

North Tide Capital Master, LP

North Tide Capital, LLC

Conan Laughlin

(b)

Address of Principal Business Office or, if none, Residence

North Tide Capital Master, LP

North Tide Capital, LLC

Conan Laughlin

500 Boylston Street, Suite 1860

Boston, Massachusetts

02116

(c)

Citizenship

North Tide Capital Master, LP – Cayman Islands

North Tide Capital, LLC – Massachusetts

Conan Laughlin – United States

(d)

Title of Class of Securities

Common Stock, $0.001 par value

(e)

CUSIP Number

81619Q105

Item 3.

If this statement is filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:

(a)

[ ]

Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).

(b)

[ ]

Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).

(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