Filing Details

THE UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 4)* Infusystem Holdings, Inc. (Name of Issuer) Common Stock, Par Value $.0001 (Title of Class of Securities) 45685K102 (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 13G is filed: [X] 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). CUSIP No. 45685K102 (1) Names of Reporting Persons. I.R.S. Identification Nos. of Above Persons (entities only): AWM Investment Company, Inc. (2) Check the Appropriate Box if a Member of a Group (See Instructions) (a)___ b)___ (3) SEC Use Only (4) Citizenship or Place of Organization: Delaware, United States Number of Shares Beneficially Owned by Each Reporting Person With (5) Sole Voting Power: 1,513,817** (6) Shared Voting Power: 0** (7) Sole Dispositive Power: 1,513,817** (8) Shared Dispositive Power: 0** (9) Aggregate Amount Beneficially Owned by Each Reporting Person: 1,513,817** (10) Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions): (11) Percent of Class Represented by Amount in Row (9): 6.6%** (12) Type of Reporting Person (See Instructions): IA **AWM Investment Company, Inc., a Delaware corporation (?AWM?), is the investment adviser to Special Situations Life Sciences Fund, L.P. (?SSLS?) (SSLS will hereafter be referred to as the ?Fund?). As the investment adviser to the Fund, AWM holds sole voting and investment power over 1,513,817 Shares held by SSLS. Austin W. Marxe (?Marxe?), David M. Greenhouse (?Greenhouse?) and Adam C. Stettner (?Stettner?) previously reported the Shares held by the Fund on Schedule 13G. Accordingly, reference should be made to Marxe, Greenhouse and Stettner (CIK #0001044321) for filings prior to February 14, 2015 with the Securities and Exchange Commission relating to the Shares held by each of the Funds. See Items 2 and 4 of this Schedule for additional information. Item 1(a). Name Of Issuer: Infusystem Holdings, Inc. Item 1(b). Address of Issuer?s Principal Executive Offices: 31700 Research Park Drive Madison Heights, Michigan 48071 Item 2(a). Name of Person Filing: The person filing this report is AWM Investment Company, Inc., a Delaware corporation (?AWM?), which is the investment adviser to Special Situations Life Sciences Fund, L.P. a Delaware limited partnership (?SSLS?),(SSLS, will hereafter be referred to as the ?Fund?). The principal business of the Fund is to invest in equity and equity-related securities and other securities of any kind or nature. Austin W. Marxe (?Marxe?), David M. Greenhouse (?Greenhouse?) and Adam C. Stettner (?Stettner?) are members of LS Advisers, L.LC., a New York limited liability company (?LS?),. Marxe, Greenhouse and Stettner are also controlling principals of AWM. Item 2(b). Address of Principal Business Office or, if None, Residence: The principal business address for AWM is c/o Special Situations Funds, 527 Madison Avenue, Suite 2600, New York, NY 10022. Item 2(c). Citizenship: AWM is a Delaware Corporation. Item 2(d). Title of Class of Securities: Common Stock, Par Value $.0001 Item 2(e). CUSIP No.: 45685K102 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: Not Applicable.

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