UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 37)

CDI Corp.

(Name of Issuer)

Common Stock, Par Value $0.10 Per Share

(Title of Class of Securities)

125071 10 0

(CUSIP Number)

December 31, 2017

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

☐ Rule 13d-1(b)

☐ Rule 13d-1(c)

☒ Rule 13d-1(d)

*	The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13G FILED BY

Trustees of Various Trusts

for the Benefit of Walter R. Garrison’s Children

PURSUANT TO THE

SECURITIES EXCHANGE ACT OF 1934

Item 1(a).

Name of Issuer:

CDI Corp.

Item 1(b).

Address of Issuer’s Principal Executive Offices:

1735 Market Street, Suite 200, Philadelphia, PA 19103

Item 2(a).

Name of Person Filing:

Lawrence C. Karlson and Barton J. Winokur, as Trustees of certain Trusts for the benefit of Susan K. Garrison, Mark R. Garrison, Pamela G. Phelan and C. Jeffrey Garrison, and Michael J. Emmi, Donald W. Garrison, Lawrence C. Karlson and Barton J. Winokur, as Trustees of certain other Trusts for the benefit of Susan K. Garrison, Mark R. Garrison, Pamela G. Phelan and C. Jeffrey Garrison

Item 2(b).

Address of Principal Business Office or, if none, Residence:

c/o Megan K. Horwitz, Esquire, Dechert LLP, Cira Centre, 2929 Arch Street, Philadelphia, PA 19104-2808

Item 2(c).

Citizenship:

United States of America, as to all Trustees

Item 2(d).

Title of Class of Securities:

Common Stock, $0.10 par value

Item 2(e).

CUSIP Number:

125071 10 0

Item 3.

Not Applicable

Item 4.

Ownership:

As of December 31, 2017:

(a)

Amount Beneficially Owned: 0 shares

(b)

Percent of Class: Not applicable

(c)

Number of shares as to which such person has:

(i)

sole power to vote or direct the vote: 0

(ii)

shared power to vote or direct the vote: 0

(iii)

sole power to dispose or direct the disposition of: 0

(iv)

shared power to dispose of: 0

Item 5.

Ownership of Five Percent or Less of a Class:

☒

Item 6.

Ownership of More than Five Percent on Behalf of Another Person:

Not applicable

Item 7.

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person:

Not applicable

Item 8.

Identification and Classification of Members of the Group:

Not applicable

Item 9.

Notice of Dissolution of Group:

Not applicable

Item 10.

Certifications:

Not applicable

Signature

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated: February 1, 2018

/s/ MICHAEL J. EMMI

Michael J. Emmi, as a Trustee

/s/ DONALD W. GARRISON

Donald W. Garrison, as a Trustee

/s/ LAWRENCE C. KARLSON

Lawrence C. Karlson, as a Trustee

/s/ BARTON J. WINOKUR

Barton J. Winokur, as a Trustee

NAMES OF REPORTING PERSONS

Lawrence C. Karlson and Barton J. Winokur, as Trustees of certain Trusts for the benefit of Susan K. Garrison, Mark R. Garrison, Pamela G. Phelan and C. Jeffrey Garrison, and Michael J. Emmi, Donald W. Garrison, Lawrence C. Karlson and Barton J. Winokur, as Trustees of certain other Trusts for the benefit of Susan K. Garrison, Mark R. Garrison, Pamela G. Phelan and C. Jeffrey Garrison

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

(a) ☐ (b) ☒

SEC USE ONLY

CITIZENSHIP OR PLACE OF ORGANIZATION

United States of America, as to all Trustees

CDI CORP SC 13G/A