13D Filing: GAMCO Investors and Guidance Software Inc. (GUID)

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

Guidance Software, Inc.

(Name of Issuer)

Common Stock, $0.001 par value per share

(Title of Class of Securities)

                                                                                                       ________401692108_________

David Goldman

GAMCO Investors, Inc.

One Corporate Center

Rye, New York 10580-1435

(914) 921-5000

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

______________________ August 30, 2017________________________

(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  .

CUSIP No. 401692108

CUSIP No. 401692108

CUSIP No. 401692108

CUSIP No. 401692108

CUSIP No. 401692108

CUSIP No. 401692108

CUSIP No. 401692108

CUSIP No. 401692108

The class of equity securities to which this statement on Schedule 13D relates is the Common Stock of Guidance Software, Inc. (the “Issuer”), a Delaware corporation with principal offices located at 1055 E. Colorado Blvd., Pasadena, CA  91106.

Item 2 to Schedule 13D is amended, in pertinent part, as follows:

This statement is being filed by Mario J. Gabelli (“Mario Gabelli”) and various entities which he

directly or indirectly controls or for which he acts as chief investment officer.  These entities, except for LICT Corporation (“LICT), CIBL, Inc. (“CIBL”) and ICTC Group, Inc. (“ICTC”), engage in various aspects of the securities business, primarily as investment adviser to various institutional and individual clients, including registered investment companies and pension plans, and as general partner or the equivalent of various private investment partnerships or private funds.  Certain of these entities may also make investments for their own accounts.

The foregoing persons in the aggregate often own beneficially more than 5% of a class of equity securities of a particular issuer.  Although several of the foregoing persons are treated as institutional investors for purposes of reporting their beneficial ownership on the short-form Schedule 13G, the holdings of those who do not qualify as institutional investors may exceed the 1% threshold presented for filing on Schedule 13G or implementation of their investment philosophy may from time to time require action which could be viewed as not completely passive.  In order to avoid any question as to whether their beneficial ownership is being reported on the proper form and in order to provide greater investment flexibility and administrative uniformity, these persons have decided to file their beneficial ownership reports on the more detailed Schedule 13D form rather than on the short-form Schedule 13G and thereby to provide more expansive disclosure than may be necessary.

(a), (b) and (c) – This statement is being filed by one or more of the following persons: GGCP, Inc.  (“GGCP”), GGCP Holdings LLC (“GGCP Holdings”), GAMCO Investors, Inc. (“GBL”), Associated Capital Group, Inc. (“AC”), Gabelli Funds, LLC (“Gabelli Funds”), GAMCO Asset Management Inc. (“GAMCO”), Teton Advisors, Inc. (“Teton Advisors”), Gabelli & Company Investment Advisers, Inc. (“GCIA”), G.research, LLC (“G.research”), MJG Associates, Inc. (“MJG Associates”), Gabelli Foundation, Inc. (“Foundation”), MJG-IV Limited Partnership (“MJG-IV”),  Mario Gabelli, LICT, CIBL and ICTC.  Those of the foregoing persons signing this Schedule 13D are hereinafter referred to as the “Reporting Persons”.

GGCP makes investments for its own account and is the manager and a member of GGCP Holdings which is the controlling shareholder of GBL and AC.  GBL, a public company listed on the New York Stock Exchange, is the parent company for a variety of companies engaged in the securities business, including certain of those named below.  AC, a public company listed on the New York Stock Exchange, is the parent company for a variety of companies engaged in the securities business, including certain of those listed below.

GAMCO, a wholly-owned subsidiary of GBL, is an investment adviser registered under the Investment Advisers Act of 1940, as amended (“Advisers Act”).  GAMCO is an investment manager providing discretionary managed account services for employee benefit plans, private investors, endowments, foundations and others.

GCIA, a wholly owned subsidiary of AC, is an investment adviser registered under the Advisers Act and serves as a general partner or investment manager to limited partnerships and offshore investment companies and other accounts.  As a part of its business, GCIA may purchase or sell securities for its own account.  GCIA is a general partner or investment manager of a number of funds or partnerships, including Gabelli Associates Fund, L.P., Gabelli Associates Fund II, L.P., Gabelli Associates Limited, Gabelli Associates Limited II E, ALCE Partners, L.P., Gabelli Capital Structure Arbitrage Fund LP, Gabelli Capital Structure Arbitrage Fund Limited, Gabelli Intermediate Credit Fund L.P., GAMA Select Energy + L.P., GAMCO Medical Opportunities L.P., and Gabelli Multimedia Partners, L.P.

G.research, a wholly owned subsidiary of GCIA, is a broker-dealer registered under the Securities Exchange Act of 1934, as amended (“1934 Act”), which as a part of its business regularly purchases and sells securities for its own account.

Gabelli Funds, a wholly owned subsidiary of GBL, is a limited liability company. Gabelli Funds is an investment adviser registered under the Advisers Act which provides advisory services for The Gabelli Equity Trust Inc., The Gabelli Asset Fund, The GAMCO Growth Fund, The Gabelli Convertible and Income Securities Fund Inc., The Gabelli Value 25 Fund Inc., The Gabelli Small Cap Growth Fund, The Gabelli Equity Income Fund, The Gabelli ABC Fund, The Gabelli Global Content & Connectivity Fund, The Gabelli Gold Fund, Inc., The Gabelli Multimedia Trust Inc., The Gabelli Global Rising Income & Dividend Fund, The Gabelli Capital Asset Fund, The GAMCO International Growth Fund, Inc., The GAMCO Global Growth Fund, The Gabelli Utility Trust, The Gabelli International Small Cap Fund, The Gabelli Utilities Fund, The Gabelli Dividend Growth Fund, The GAMCO Mathers Fund, The Gabelli Focus Five Fund, The Comstock Capital Value Fund, The Gabelli Dividend and Income Trust, The Gabelli Global Utility & Income Trust, The GAMCO Global Gold, Natural Resources, & Income Trust, The GAMCO Natural Resources Gold & Income Trust, The GDL Fund, Gabelli Enterprise Mergers & Acquisitions Fund, The Gabelli ESG Fund, Inc., The Gabelli Healthcare & Wellness ^Rx Trust, The Gabelli Global Small and Mid Cap Value Trust, Gabelli Value Plus+ Trust, Gabelli Merger Plus+ Trust, The Gabelli Go Anywhere Trust, Bancroft Fund Ltd. and Ellsworth Growth & Income Fund Ltd. (collectively, the “Funds”), which are registered investment companies.  Gabelli Funds is also the investment adviser to the Gabelli Media Mogul NextShares, the Gabelli Food of All Nations NextShares and The GAMCO International SICAV (sub-funds GAMCO Merger Arbitrage and GAMCO All Cap Value), a UCITS III vehicle.

Teton Advisors, an investment adviser registered under the Advisers Act, provides discretionary advisory services to The TETON Westwood Mighty Mites^sm Fund, The TETON Westwood Income Fund, The TETON Westwood SmallCap Equity Fund, The TETON Westwood Mid-Cap Equity Fund, and The TETON Westwood Intermediate Bond Fund.

MJG Associates provides advisory services to private investment partnerships and offshore funds.  Mario Gabelli is the sole shareholder, director and employee of MJG Associates.   MJG Associates is the Investment Manager of Gabelli International Limited and Gabelli Fund, LDC.  Mario J. Gabelli is the general partner of Gabelli Performance Partnership, LP.

The Foundation is a private foundation.  Mario Gabelli is the Chairman, a Trustee and the Investment Manager of the Foundation. Elisa M. Wilson is the President of the Foundation.

LICT is a holding company with operating subsidiaries engaged primarily in the rural telephone industry. LICT actively pursues new business ventures and acquisitions. LICT makes investments in marketable securities to preserve capital and maintain liquidity for financing their business activities and acquisitions and are not engaged in the business of investing, or trading in securities. Mario J. Gabelli is the Chief Executive Officer, a director, and substantial shareholder of LICT.

ICTC is a holding company with subsidiaries in voice, broadband and other telecommunications services, primarily in the rural telephone industry. ICTC makes investments in marketable securities to preserve capital and maintain liquidity for financing their business activities and acquisitions and are not engaged in the business of investing, or trading in securities. Mario J. Gabelli is a director, and substantial shareholder of ICTC.

CIBL is a holding company with interests in telecommunications operations, primarily in the rural telephone industry. CIBL actively pursues new business ventures and acquisitions. CIBL makes investments in marketable securities to preserve capital and maintain liquidity for financing their business activities and acquisitions and are not engaged in the business of investing, or trading in securities. Mario J. Gabelli is a director, and substantial shareholder of CIBL.

Mario Gabelli is the controlling stockholder, Chief Executive Officer and a director of GGCP and Chairman and Chief Executive Officer of GBL. He is the Executive Chairman of AC.  Mario Gabelli is also a member of GGCP Holdings. Mario Gabelli is the controlling shareholder of Teton.

                             MJG-IV is a family partnership in which Mario Gabelli is the general partner.  Mario Gabelli has less than a 100% interest in MJG-IV.  MJG-IV makes investments for its own account.  Mario Gabelli disclaims ownership of the securities held by MJG-IV beyond his pecuniary interest.

The Reporting Persons do not admit that they constitute a group.

GAMCO is a New York corporation and GBL, AC, GCIA, and Teton Advisors are Delaware corporations, each having its principal business office at One Corporate Center, Rye, New York 10580. GGCP is a Wyoming corporation having its principal business office at 140 Greenwich Avenue, Greenwich, CT 06830.   GGCP Holdings is a Delaware limited liability corporation having its principal business office at 140 Greenwich Avenue, Greenwich, CT 06830.  G.research is a Delaware limited liability company having its principal officers at One Corporate Center, Rye, New York 10580.  Gabelli Funds is a New York limited liability company having its principal business office at One Corporate Center, Rye, New York 10580.  MJG Associates is a Connecticut corporation having its principal business office at 140 Greenwich Avenue, Greenwich, CT 06830.  The Foundation is a Nevada corporation having its principal offices at 165 West Liberty Street, Reno, Nevada 89501.  LICT is a Delaware corporation having its principal place of business as 401 Theodore Fremd Avenue, Rye, New York 10580. CIBL, Inc. is a Delaware corporation having its principal place of business as 165 West Liberty Street, Suite 220, Reno, NV 89501.  ICTC Group Inc. is a Delaware corporation having its principal place of business as 556 Main Street, Nome, North Dakota 58062.

For information required by instruction C to Schedule 13D with respect to the executive officers and directors of the foregoing entities and other related persons (collectively, “Covered Persons”), reference is made to Schedule I annexed hereto and incorporated herein by reference.

(d) – Not applicable.

(e) – Not applicable.

The Reporting Persons used an aggregate of approximately $5,571,607 to purchase the Securities reported as beneficially owned in Item 5. GAMCO and Gabelli Funds used approximately $140,830 and $2,471,482,  respectively, of funds that were provided through the accounts of certain of their investment advisory clients (and, in the case of some of such accounts at GAMCO, may be through borrowings from client margin accounts) in order to purchase the Securities for such clients. GCIA used approximately $2,959,295 of client funds to purchase the Securities reported by it.

 Each of the Reporting Persons has purchased and holds the Securities reported by it for investment for one or more accounts over which it has shared, sole, or both investment and/or voting power, for its own account, or both.

The Reporting Persons are engaged in the business of securities analysis and investment. The Reporting Persons analyze the operations, capital structure and markets of companies in which they invest, including the Issuer, on a continuous basis through analysis of documentation and discussions with knowledgeable industry and market observers and with representatives of such companies (often at the invitation of management).  As a result of these analytical activities one or more of the Reporting Persons may issue analysts reports, participate in interviews or hold discussions with third parties, with management or with Directors in which the Reporting Person may suggest or take a position with respect to potential changes in the operations, management or capital structure of such companies as a means of enhancing shareholder values.  Such suggestions or positions may relate to one or more of the transactions specified in clauses (a) through (j) of Item 4 of Schedule 13D including, without limitation, such matters as disposing of one or more businesses, selling the company or acquiring another company or business, changing operating or marketing strategies, adopting or not adopting, certain types of anti-takeover measures and restructuring the company’s capitalization or dividend policy.

Each of the Reporting Persons intends to adhere to the foregoing investment philosophy with respect to the Issuer.  However, none of the Reporting Persons intends to seek control of the Issuer or participate in the management of the Issuer, and any Reporting Person that is registered as an investment company under the Company Act will participate in such a transaction only following receipt of an exemption from the SEC under Rule 17d-1 under the Company Act, if required, and in accordance with other applicable law.  In pursuing this investment philosophy, each Reporting Person will continuously assess the Issuer’s business, financial condition, results of operations and prospects, general economic conditions, the securities markets in general and those for the Issuer’s securities in particular, other developments and other investment opportunities, as well as the investment objectives and diversification requirements of its shareholders or clients and its fiduciary duties to such shareholders or clients.  Depending on such assessments, one or more of the Reporting Persons may acquire additional Securities or may determine to sell or otherwise dispose of all or some of its holdings of Securities.  Although the Reporting Persons share the same basic investment philosophy and although most portfolio decisions are made by or under the supervision of Mario Gabelli, the investment objectives and diversification requirements of various clients differ from those of other clients so that one or more Reporting Persons may be acquiring Securities while others are disposing of Securities.

With respect to voting of the Securities, the Reporting Persons have adopted general voting policies relating to voting on specified issues affecting corporate governance and shareholder values.  Under these policies, the Reporting Persons generally vote all securities over which they have voting power in favor of cumulative voting, financially reasonable golden parachutes, one share one vote, management cash incentives and pre-emptive rights and against greenmail, poison pills, supermajority voting, blank check preferred stock and super-dilutive stock options.  Exceptions may be made when management otherwise demonstrates superior sensitivity to the needs of shareholders.  In the event that the aggregate voting position of all Reporting Persons exceeds 25% of the total voting position of the Issuer, one or more of the filing persons may transfer voting and/or dispositive power over shares to independent committees of directors or the owners of such shares. Such committees vote and/or consider disposition of such shares independently of the Reporting Persons.

Each of the Covered Persons who is not a Reporting Person has purchased the Securities reported herein as beneficially owned by him for investment for his own account or that of one or more members of his immediate family.  Each such person may acquire additional Securities or dispose of some or all of the Securities reported herein with respect to him.

Other than as described above, none of the Reporting Persons and none of the Covered Persons who is not a Reporting Person has any present plans or proposals which relate to or would result in any transaction, change or event specified in clauses (a) through (j) of Item 4 of Schedule 13D.

(a) The aggregate number of Securities to which this Schedule 13D relates is 1,716,567 shares, representing 5.13% of the 33,431,000 shares outstanding as reported by the Issuer in its Form 10-Q for the quarterly period ended June 30, 2017.   The Reporting Persons beneficially own those Securities as follows:

Mario Gabelli is deemed to have beneficial ownership of the Securities owned beneficially by each of the foregoing persons.  GCIA is deemed to have beneficial ownership of the Securities owned beneficially by G.research.  AC, GBL and GGCP are deemed to have beneficial ownership of the Securities owned beneficially by each of the foregoing persons other than Mario Gabelli and the Foundation.

(b) Each of the Reporting Persons and Covered Persons has the sole power to vote or direct the vote and sole power to dispose or to direct the disposition of the Securities reported for it, either for its own benefit or for the benefit of its investment clients or its partners, as the case may be, except that , (i) Gabelli Funds has sole dispositive and voting power with respect to the shares of the Issuer held by the Funds so long as the aggregate voting interest of all joint filers does not exceed 25% of their total voting interest in the Issuer and, in that event, the Proxy Voting Committee of each Fund shall respectively vote that Fund’s shares, (ii) at any time, the Proxy Voting Committee of each such Fund may take and exercise in its sole discretion the entire voting power with respect to the shares held by such fund under special  circumstances such as regulatory considerations, and (iii) the power of Mario Gabelli, AC, GBL, and GGCP is indirect with respect to Securities beneficially owned directly by other Reporting Persons.

(c) Information with respect to all transactions in the Securities which were effected during the past sixty days or since the most recent filing on Schedule 13D, whichever is less, by each of the Reporting Persons and Covered Persons is set forth on Schedule II annexed hereto and incorporated herein by reference.

(e) Not applicable.

The powers of disposition and voting of Gabelli Funds, Teton Advisors, GAMCO, GCIA and MJG Associates with respect to Securities owned beneficially by them on behalf of their investment advisory clients, and of MJG Associates and GCIA with respect to Securities owned beneficially by them on behalf of the partnerships or corporations which they directly or indirectly manage, are held pursuant to written agreements with such clients, partnerships and funds.

The following Exhibit A is attached hereto.  The following Exhibit B is incorporated by reference to Exhibit B in the Initial Schedule 13D of the Reporting Persons with respect to Lincare Holdings Inc.

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: September 7, 2017

GGCP, INC.

MARIO J. GABELLI

By:/s/ David Goldman

     David Goldman

     Attorney-in-Fact

TETON ADVISORS, INC.

GABELLI FUNDS, LLC

     David Goldman

     General Counsel – Gabelli Funds, LLC

    Counsel-Teton Advisors, Inc.

  GAMCO INVESTORS, INC.

     Kevin Handwerker

                General Counsel & Secretary – GAMCO Investors, Inc.

ASSOCIATED CAPITAL GROUP, INC.

GAMCO ASSET MANAGEMENT INC.

GABELLI & COMPANY INVESTMENT ADVISERS, INC.

     Douglas R. Jamieson

                    President & Chief Executive Officer – Associated Capital

Group, Inc.

      President – GAMCO Asset Management Inc.

      President – Gabelli & Company Investment Advisers, Inc.

SCHEDULE I

     Information with Respect to Executive

Schedule I to Schedule 13D is amended, in pertinent part, as follows:

                               SCHEDULE II

                            INFORMATION WITH RESPECT TO

                 TRANSACTIONS EFFECTED DURING THE PAST SIXTY DAYS OR

                 SINCE THE MOST RECENT FILING ON SCHEDULE 13D (1)

                                   SHARES PURCHASED        AVERAGE

                        DATE            SOLD(-)             PRICE(2)

 COMMON STOCK-GUIDANCE SOFTWARE, INC.

          GABELLI & COMPANY INVESTMENT ADVISERS, INC.

                       8/30/17           14,000             7.0700

                       8/28/17            1,100             7.0800

                       8/15/17            5,000             7.0600

                       8/08/17            4,000             7.0699

                       8/07/17           10,800             7.0719

                       8/04/17            3,000             7.0681

                       8/03/17            2,900             7.0699

                       8/01/17            1,600             7.0791

                       7/31/17           11,300             7.0764

                       7/27/17           27,600             7.0910

                       7/26/17           20,100             7.1033

             GABELLI ASSOCIATES LIMITED II E

                       8/30/17            7,800             7.0700

                       8/28/17              600             7.0800

                       8/15/17            2,900             7.0600

                       8/08/17            2,100             7.0699

                       8/07/17            6,200             7.0719

                       8/04/17            1,600             7.0681

                       8/03/17            1,600             7.0699

                       8/01/17            1,000             7.0791

                       7/31/17            5,900             7.0764

                       7/27/17           15,700             7.0910

                       7/26/17           11,300             7.1033

             GABELLI ASSOCIATES LIMITED

                       8/30/17           13,100             7.0700

                       8/28/17            1,100             7.0800

                       8/15/17            4,800             7.0600

                       8/08/17            3,700             7.0699

                       8/07/17           10,300             7.0719

                       8/04/17            2,800             7.0681

                       8/03/17            2,800             7.0699

                       8/01/17            1,600             7.0791

                       7/31/17           10,600             7.0764

                       7/27/17           26,100             7.0910

                       7/26/17           18,906             7.1033

             GABELLI ASSOCIATES FUND II

                       8/30/17            5,500             7.0700

                       8/28/17              500             7.0800

                       8/15/17            2,100             7.0600

                       8/08/17            1,500             7.0699

                       8/07/17            4,400             7.0719

                       8/04/17            1,100             7.0681

                       8/03/17            1,200             7.0699

                       8/01/17              600             7.0791

                       7/31/17            4,400             7.0764

                       7/27/17           11,000             7.0910

                       7/26/17            8,000             7.1033

             GABELLI ASSOCIATES FUND

                       8/30/17           17,100             7.0700

                       8/28/17            1,300             7.0800

                       8/15/17            6,300             7.0600

                       8/08/17            4,700             7.0699

                       8/07/17           13,300             7.0719

                       8/04/17            3,500             7.0681

                       8/03/17            3,701             7.0699

                       8/01/17            2,000             7.0791

                       7/31/17           13,700             7.0764

                       7/27/17           33,600             7.0910

                       7/26/17           24,400             7.1033                                                                                             

          GAMCO ASSET MANAGEMENT INC.

                       8/28/17              400             7.0800

                       8/15/17            1,227             7.0600

                       8/10/17            5,000-            7.0631

                       8/08/17              945             7.0699

                       8/03/17              799             7.0699

                       8/01/17              300             7.0791

                       7/31/17            2,610             7.0764

                       7/27/17            6,434             7.0910

                       7/27/17           13,000             7.0965

                       7/26/17           11,000             7.1099

                       7/26/17            4,650             7.1033

                       7/26/17           44,000             7.1195

          GABELLI FUNDS, LLC.

             GABELLI MERGER PLUS+ TRUST

                       8/30/17           10,000             7.0700

                       8/07/17           10,000             7.0719

                       8/04/17            5,000             7.0681

                       8/02/17            8,300             7.0700

                       7/31/17           10,000             7.0764

                       7/27/17           15,000             7.0910

             GABELLI GO ANYWHERE TRUST

                       7/28/17            5,000             7.0800

                       7/27/17            2,500             7.0965

                       7/26/17            2,500             7.1099

             THE GDL FUND

                       7/27/17           18,000             7.0965

                       7/26/17           15,000             7.1099

             GABELLI ENTERPRISE M&A FUND

                       7/27/17            9,000             7.0965

                       7/26/17            7,000             7.1099

             GAMCO MERGER ARBITRAGE

                       8/30/17           29,169             7.0700

                       8/28/17            5,000             7.0800

                       8/15/17           10,709             7.0600

                       8/14/17            4,722             7.0600

                       8/08/17            8,157             7.0699

                       8/07/17           22,515             7.0719

                       8/04/17            7,180             7.0681

                       8/03/17            7,000             7.0699

                       8/01/17            3,600             7.0791

                       7/31/17           23,738             7.0764

                       7/27/17           55,413             7.0910

                       7/26/17           40,532             7.1033

             GAMCO ALL CAP VALUE

                       7/27/17              500             7.0965

                       7/26/17              500             7.1099

             GABELLI ABC FUND

                       7/27/17           77,000             7.0965

                       7/26/17           64,000             7.1099

(1) UNLESS OTHERWISE INDICATED, ALL TRANSACTIONS WERE EFFECTED

    ON THE NASDAQ GLOBAL SECURITIES MARKET.

(2) PRICE EXCLUDES COMMISSION.

(*) RESULTS IN CHANGE OF DISPOSITIVE POWER AND BENEFICIAL OWNERSHIP.

In accordance with Rule 13d-1(f) under the securities Exchange Act of 1934, as amended, the undersigned hereby agree to the joint filing with all other Reporting Entities (as such term is defined in the Schedule 13D referred to below) on behalf of each of them of a statement on Schedule 13D (including amendments thereto) with respect to the Common Stock of Guidance Software, Inc. and that this Agreement be included as an Exhibit to such joint filing.  This Agreement may be executed in any number of counterparts all of which taken together shall constitute one and the same instrument.

IN WITNESS WHEREOF, the undersigned hereby execute this Agreement this September 7, 2017.