UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

(Rule 13d-101)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO § 240.13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO

§ 240.13d-2(a)

(Amendment No. 5)¹

InfuSystem Holdings, Inc.

(Name of Issuer)

Common Stock, par value $0.0001 per share

(Title of Class of Securities)

45685K102

(CUSIP Number)

RYAN J. MORRIS

MESON CAPITAL PARTNERS LLC

One Sansome Street, Suite 1895

San Francisco, California 94104

(607) 279-5382

(Name, Address and Telephone Number of Person

Authorized to Receive Notices and Communications)

July 23, 2018

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box ¨.

Note:  Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits.  See § 240.13d-7 for other parties to whom copies are to be sent.

1              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 disclosures provided in a prior cover page.

The information required on 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).

The following constitutes Amendment No. 5 to the Schedule 13D filed by the undersigned (“Amendment No. 5”). This Amendment No. 5 amends the Schedule 13D as specifically set forth herein.

Item 2 is hereby amended to add the following:

In connection with the completion of the Issuer’s 2018 annual meeting of stockholders (the “Annual Meeting”) held on July 19, 2018, Mohamed Alkady, Daniel Balda, Bryan Boches, Richard Linder and Asha Saxena are no longer members of the Section 13(d) group and shall cease to be Reporting Persons immediately upon the filing of this Amendment No. 5 to the Schedule 13D. The remaining Reporting Persons will continue filing statements on Schedule 13D with respect to their beneficial ownership of securities of the Issuer to the extent required by applicable law. Each of the remaining Reporting Persons is party to the Joint Filing Agreement, as further described in Item 6 below.

Item 4 is hereby amended to add the following:

As of the date hereof, Meson and Argonne are withdrawing their non-binding proposal to acquire the Issuer originally submitted on June 15, 2018. The proposal is withdrawn due to the Board’s rejection of the proposal on June 19, 2018 and the outcome of the election of directors at the Annual Meeting. At this time the remaining Reporting Persons are considering all potential courses of action in connection with the Issuer and it’s securities, including, but not limited to, submitting another proposal, inviting other stockholders to join with them in submitting a proposal, increasing or decreasing their ownership in the Issuer through transactions on the open market or in private transactions or otherwise, and taking certain other actions which could involve one or more of the types of transactions or have one or more of the results described in Items 4(a) through (j) of Schedule 13D. 

Item 6 is hereby amended to add the following:

On July 23, 2018, the Reporting Persons entered into a Joint Filing Agreement in which the Reporting Persons who will remain Reporting Persons subsequent to this Amendment No. 5 to the Schedule 13D agreed to the joint filing on behalf of each of them of statements on Schedule 13D with respect to the securities of the Issuer to the extent required by applicable law. A copy of the Joint Filing Agreement is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

Item 7 is hereby amended to add the following exhibits:

SIGNATURES

After reasonable inquiry and to the best of his knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

Dated: July 23, 2018

Exhibit 99.1

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k)(iii) under the Securities Exchange Act of 1934, as amended, persons named below agree to the joint filing on behalf of each of them of a Statement on Schedule 13D (including additional amendments thereto) with respect to the shares of Common Stock, par value $0.0001 per share, of InfuSystem Holdings, Inc., a Delaware corporation, and further agree that this Joint Filing Agreement shall be filed as an Exhibit to such Statement.

Dated: July 23, 2018