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Exhibit 4.3 Placement Agent Registration Rights Agreement

                          REGISTRATION RIGHTS AGREEMENT

         THIS REGISTRATION RIGHTS AGREEMENT ("Agreement") is made as of August
22, 2001, by and among American Bio Medica Corporation, a New York corporation
(the "Company"), and the persons signing the signature page of this Agreement
who have acted as placement agent or sub-agents (the "Placement Agents") in
connection with the August 2001 private placement of the Company's common
shares.

                                    RECITALS

         A. Pursuant to an engagement letter (the "Engagement Letter"), dated
June 4, 2001, the Placement Agents have been issued warrants (the "Common Stock
Warrants") entitling the holders thereof to purchase the number of shares (the
"Warrant Shares") of Common Stock as set forth therein.

         B. The Company has agreed to provide the Placement Agents with certain
registration rights described herein.

         THEREFORE, in consideration of the promises and the mutual covenants
and agreements contained in the Engagement Letter and other good and valuable
consideration, receipt of which is hereby acknowledged, the parties hereby agree
as follows:

         1. Definitions. For purposes of this Agreement, the following terms
shall have the following meanings:

            Person. An individual, partnership, corporation, limited liability
         company, trust or unincorporated organization, or a government or
         agency or political subdivision thereof.

            Prospectus. The prospectus included in any Registration Statement,
         as amended or supplemented by any prospectus supplement, including
         post-effective amendments and all material incorporated by reference in
         the prospectus.

            Registration Statement. Any registration statement of the Company
         which covers any of the Registrable Securities (as defined in Section 2
         hereof) pursuant to the provisions of this Agreement, including the
         registration statement and amendments and post-effective amendments
         thereto, the Prospectus and supplements therein, all exhibits and all
         material incorporated by reference in the registration statement.

            SEC. The U.S. Securities and Exchange Commission.

            Securities Act. The Securities Act of 1933, as amended.

            Shares. The Common Shares and the Warrant Shares.
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         2. Securities Subject to this Agreement. The securities entitled to the
benefit of this Agreement are all the Common Shares issuable upon exercise of
the Common Stock Warrants (the "Registrable Securities"); provided, however,
that the Common Shares issuable upon exercise of the Common Stock Warrants shall
be Registrable Securities only for so long as the Common Shares continue to be
Restricted Securities. For purposes of this Agreement, the Common Shares
issuable upon exercise of the Common Stock Warrants shall be Restricted
Securities as of the date of this Agreement. The Common Shares issuable upon
exercise of the Common Stock Warrants shall cease to be Restricted Securities
when (1) the Company has effectively registered the Common Shares issuable upon
exercise of the Common Stock Warrants under the Securities Act and the Placement
Agents who own the Common Shares issuable upon the exercise of the Common Stock
Warrants, have disposed of the Common Shares issuable upon exercise of the
Common Stock Warrants in accordance with the Registration Statement covering the
Common Shares issuable upon exercise of the Common Stock Warrants, (2) the
Placement Agents who own Common Shares issuable upon the exercise of the Common
Stock Warrants, shall be eligible to sell the Common Shares issuable upon
exercise of the Common Stock Warrants to the public in accordance with all
applicable conditions of Rule 144 (or any similar provisions then in force)
under the Securities Act, or such Common Shares issuable upon the exercise of
the Common Stock Warrants may be sold pursuant to Rule 144(k) (or any similar
provision then in force) under the Securities Act, and are freely tradable after
such sale by the transferee, (3) the Placement Agents have otherwise transferred
the Common Shares issuable upon the exercise of the Common Stock Warrants
(except as otherwise provided in Section (h) hereof), or (4) such Common Shares
issuable upon the exercise of the Common Stock Warrants shall have ceased to be
outstanding.

         3. Registration of Registrable Securities. On or before the later of
(i) August 15, 2001 or (ii) the thirtieth business day after the date American
Bio Medica issues the Common Stock Warrants, the Company will use its best
efforts to cause a Registration Statement to be filed with the SEC covering the
Registrable Securities. The Company shall also use its commercially reasonable
efforts to cause such Registration Statement to become effective within 45 days
after such filing (or 90 days if reviewed by the Staff of the SEC) and, subject
to the provisions of Section 2 hereof, remain effective until two years after
the last date Common Shares issuable upon the exercise of the Common Stock
Warrants are issued to such Placement Agents pursuant to the Engagement Letter.

         4. Registration Procedures.

            (a)      The Company shall:

                     (i) furnish to the Placement Agents, without charge,
         at least one signed copy of the Registration Statement and any
         post-effective amendment thereto, including financial statements and
         schedules, all documents incorporated by reference therein and all
         exhibits (including those incorporated by reference);

                     (ii) deliver to the Placement Agents, without charge, as
         many copies of the Prospectus (including each preliminary Prospectus)
         and any amendment or supplement thereto as they may reasonably request,
         but only while the Company is required to cause the Registration
         Statement to remain effective;

                     (iii) prior to any public offering of Registrable
         Securities, register or qualify or cooperate with the Placement Agents
         and their respective counsel in connection with the registration or
         qualification of the Registrable Securities for offer and sale under
         the securities laws of the various states (the "Blue Sky Laws") and do
         any and all other acts or things reasonably necessary or advisable to
         effect the registration or qualification of the Registrable Securities
         covered by the Registration Statement in the various states; provided,
         however, that in no event shall the Company be obligated to qualify to
         do business in any jurisdiction where it is not now qualified or to
         take any action which would subject it to taxation or service of
         process in suits other than those arising out of the offer or sale of
         the securities covered by such Registration Statement in any
         jurisdictions where it is not now so subject;

                     (iv) cooperate with the Placement Agents to prepare and
         deliver timely certificates representing Registrable Securities to be
         sold and not bearing any restrictive legends; and issue the Registrable
         Securities in the denominations and register them in the names the
         Placement Agents may request at least two (2) business days prior to
         any sale of Registrable Securities;

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                     (v) use its best efforts to cause a Notification Form for
         Listing of Additional Shares to be filed with The Nasdaq Stock Market
         with respect to the Registrable Securities being registered or to cause
         similar required forms to be filed with the market on which similar
         securities issued by the Company are then listed or traded; and

                     (vi) make available to the Placement Agents and any
         attorney or accountant retained by the Placement Agents for inspection
         all financial and other records, pertinent corporate documents and
         properties of the Company, and cause the Company's officers, directors
         and employees to supply all information that the participating
         Placement Agents, the Placement Agents' representatives, attorneys or
         accountants may reasonably request in connection with the registration;
         provided, that such Persons shall keep confidential any records,
         information or documents that the Company designates as confidential
         unless a court or administrative agency requires the disclosure of the
         records, information or documents.

         (b) Each of the Placement Agents agree to furnish the Company with any
information regarding the Placement Agents and the distribution of the
Registrable Securities as the Company may from time to time reasonably request.

         (c) The Placement Agents agree that, upon receipt of any notice from
the Company of the happening of any of the following: (i) the SEC's issuance of
any stop order denying or suspending the effectiveness of the Registration
Statement or the initiation or threatening of any proceeding for that purpose,
(ii) the Company's receipt of any stop order denying registration or suspending
the qualification of the Registrable Securities for sale or the initiation or
threatening of any proceeding for such purpose, or (iii) the happening of any
event which makes any statement made in the Registration Statement, the
Prospectus or any document incorporated by reference therein untrue or which
requires any change in the Registration Statement, the Prospectus or any
document incorporated by reference therein to make the statements not include an
untrue statement of material fact or not omit any material fact required to be
stated therein or necessary to make the statements therein not misleading in
light of the circumstances then existing, the Placement Agents shall discontinue
the disposition of Registrable Securities until the Placement Agents receive a
supplemented or amended Prospectus from the Company or until the Company advises
the Placement Agents in writing that the participating Placement Agents may
resume the use of the Prospectus, and have received copies of any additional or
supplemental filings which are incorporated by reference in the Prospectus. If
the Company so directs, the Placement Agents will deliver to the Company all
copies, other than permanent file copies then in the Placement Agents'
possession, of the Prospectus covering the Registrable Securities at the time
the Placement Agents received the notice.

         5. Registration Expenses. Regardless of when the Registration Statement
becomes effective, the Company shall bear all costs and expenses incident to the
Company's performance of, or compliance with, this Agreement, including without
limitation all registration and filing fees, fees and expenses of compliance
with the Blue Sky Laws, printing expenses, messenger, telephone and delivery
expenses, and fees and disbursements of counsel for the Company, all independent
certified public accountants of the Company, and fees and expenses of other
Persons retained by the Company relating to the distribution of the Registrable
Securities (all such expenses being called "Registration Expenses"). The
participating Placement Agents shall in all cases bear all discounts, fees or
commissions incident to the sale of the Placement Agents' Registrable Securities
and any fees of any attorney or accountant retained by any of the Placement
Agents.

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         6. Indemnification.

            (a) Indemnification by the Company. The Company agrees to
         indemnify and hold harmless, to the full extent permitted by law, the
         Placement Agents against all losses, claims, damages, liabilities and
         expenses, joint or several, to which the Placement Agents may become
         subject under the Securities Act or any state securities law, or any
         rule or regulation promulgated under the Securities Act or otherwise
         which arise out of, or are caused by, the Company's violation of the
         Securities Act or any state securities laws, or any rule or regulation
         promulgated under the Securities Act, including, but not limited to,
         any untrue or alleged untrue statement of a material fact contained in
         any Registration Statement, Prospectus or preliminary Prospectus or in
         any application or other request that the Company files, including any
         application or request filed under the Blue Sky Laws, or any omission
         or alleged omission to state therein a material fact required to be
         stated therein or necessary to make the statements therein not
         misleading, except insofar as the same are based upon an untrue or
         alleged untrue statement or omission or alleged omission so made which
         is contained in information furnished to the Company by any of the
         Placement Agents expressly for use therein or by any Shareholder's
         failure to deliver a copy of the Registration Statement or Prospectus
         after the Company has furnished the participating Placement Agents with
         a copy of the same. The Company will reimburse the Placement Agents for
         any legal or other expense the Placement Agents reasonably incur in
         connection with investigating or defending any such loss, claim,
         damage, liability, action or proceeding. The Company will also
         indemnify the selling brokers, dealer managers and similar securities
         industry professionals participating in the distribution, their
         officers and directors and each Person who controls such persons
         (within the meaning of the Securities Act) to the same extent as
         provided above with respect to the indemnification of the Placement
         Agents, if requested.

            (b) Indemnification by the Placement Agents. In connection with any
         Registration Statement in which any Shareholder's Registrable
         Securities are registered and sold, the participating Placement Agents
         shall furnish to the Company the information and affidavits as the
         Company reasonably requests for use in connection with any Registration
         Statement or Prospectus and agree, jointly and severally, to indemnify
         and hold harmless, to the full extent permitted by law, the Company,
         its officers directors and each Person who controls the Company (within
         the meaning of the Securities Act) against any losses, claims, damages,
         liabilities and expenses resulting from any untrue or alleged untrue
         statement of a material fact or any omission or alleged omission of a
         material fact required to be stated in the Registration Statement,
         Prospectus, preliminary Prospectus or any application filed under the
         Blue Sky Laws or necessary to make the statements therein not
         misleading, to the extent, but only to the extent, that the untrue
         statement or omission is contained in any information or affidavit so
         furnished by the Shareholder to the Company specifically for inclusion
         in the Registration Statement, Prospectus or application filed under
         the Blue Sky Laws. The Company shall be entitled to receive indemnities
         from selling brokers, dealer managers and similar securities industry
         professionals participating in the distribution, to the same extent as
         provided above with respect to information so furnished by the Persons
         specifically for inclusion in any Prospectus or Registration Statement.

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            (c) Conduct of Indemnification Proceedings. Any Person entitled to
         indemnification hereunder shall (1) promptly notify the indemnifying
         party of any claim with respect to which it seeks indemnification and
         (2) permit such indemnifying party to assume the defense of such claim
         with counsel reasonably satisfactory to the indemnified party. Any
         Person entitled to indemnification hereunder shall have the right to
         employ separate counsel and to participate in the defense of the claim,
         but the fees and expenses of the counsel shall be at the expense of the
         Person unless (A) the indemnifying party has agreed to pay the fees or
         expenses, (B) the indemnifying party shall have failed to assume the
         defense of the claim and employ counsel reasonably satisfactory to the
         Person, or (C) in the reasonable judgment of the Person, based upon
         advice of its counsel, a conflict of interest may exist between the
         Person and the indemnifying party with respect to the claims (in which
         case, if the Person notifies the indemnifying party in writing that the
         Person elects to employ separate counsel at the expense of the
         indemnifying party, the indemnifying party shall not have the right to
         assume the defense of the claim on behalf of the Person). The
         indemnifying party will not be subject to any liability for any
         settlement made without its consent. The indemnifying party, however,
         may not unreasonably withhold its consent. No indemnifying party will
         be required to consent to the entry of any judgment or to enter into
         any settlement which does not include as an unconditional term the
         claimant's or plaintiff's release of the indemnified party from all
         liability in respect to the claim or litigation. An indemnifying party
         who is not entitled to, or elects not to, assume the defense of a claim
         shall not be obligated to pay the fees and expenses of more than one
         counsel for all parties indemnified by the indemnifying party with
         respect to the claim, unless in the reasonable judgment of any
         indemnified party a conflict of interest may exist between such
         indemnified party and any other of such indemnified parties with
         respect to the claim, in which event the indemnifying party shall be
         obligated to pay the fees and expenses of such additional counsel or
         counsels.

            (d) Contribution. If for any reason the indemnification provided for
         in the preceding clauses 6(a) and 6(b) is unavailable to an indemnified
         party or insufficient to hold it harmless as contemplated by the
         preceding clauses 6(a) and 6(b), then the indemnifying party shall
         contribute to the amount paid or payable by the indemnified party as a
         result of the loss, claim, damage liability or expense in the
         proportion as is appropriate to reflect (1) the relative benefits
         received by the indemnified party and the indemnifying party, (2) the
         relative fault of the indemnified party and the indemnifying party, and
         (3) any other relevant equitable considerations.

            (e) The indemnities provided in this Section 6 shall survive the
         Placement Agents' transfer of any Registrable Securities.

         7. Miscellaneous.

            (a) Other Agreements. The Placement Agents acknowledge that the
         Company has granted registration rights to others and the rights
         granted in this Agreement are subject to those rights already granted.

            (b) Amendments and Waivers. No amendment, modification, supplement
         or waiver of any provision of this Agreement is binding on any party
         unless the party consents in writing thereto.

            (c) Notices. Any notice or other communication required or which may
         be given under this Agreement shall be in writing and either delivered
         personally to the addressee, telegraphed, telecopied or telexed to the
         addressee, sent by overnight courier to the addressee or mailed,
         certified or registered mail, postage prepaid, and shall be deemed
         given when so delivered personally, telegraphed, telecopied or telexed
         to the addressee, or, if sent by overnight courier, on the day delivery
         is guaranteed by such courier, or, if mailed, three business days after
         the date of mailing, as follows:

                (i) to the Placement Agents, at the most current address given
            by the Placement Agents to the Company pursuant to the Subscription
            Agreements or otherwise.

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                           (ii)     To American Bio Medica at:

                                    American Bio Medica Corporation
                                    122 Smith Road
                                    Kinderhook, New York 12106
                                    Attention:  President

                                    With a copy to:

                                    Fulbright & Jaworski L.L.P.
                                    666 Fifth Avenue
                                    New York, New York 10103
                                    Attention: Neil Gold, Esq.

         Any of the foregoing may change its address for notices by notice to
the other parties.

            (d) Governing Law and Forum. The laws of the State of New York shall
         govern this Agreement, its construction, and the determination of any
         rights, duties or remedies of the parties arising out of, or relating
         to, this Agreement (regardless of the laws that might otherwise govern
         under applicable New York principles of conflicts of law). The parties
         acknowledge that the United States District Court for the Southern
         District of New York or the New York Supreme Court for the County of
         Columbia shall have exclusive jurisdiction over any case or controversy
         arising out of, or relating to, this Agreement and that all litigation
         arising out of, or relating to, this Agreement shall be commenced in
         the United States District Court for the Southern District of New York
         or in the Columbia County (New York) Supreme Court. Each of the parties
         consents to be subject to personal jurisdiction of the courts of New
         York, including the federal courts in New York.

            (e) Counterparts. This Agreement may be executed in two or more
         counterparts, each of which shall be deemed an original, but all of
         which together shall constitute one and the same instrument.

            (f) Interpretation. The Section headings contained in this Agreement
         are for the purposes of reference, are not part of the agreement of the
         parties and shall not in any way affect the meaning or interpretation
         of this Agreement.

            (g) Severability. If any provision of this Agreement is determined
         to be illegal or invalid, such illegality or invalidity shall have no
         effect on the other provisions of this Agreement, and all other
         provisions of this Agreement shall remain valid, operative and
         enforceable.

            (h) Assignment. The rights granted to the Placement Agents pursuant
         to this Agreement shall not be assignable without the written consent
         of the Company.

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         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first written above.

                                            AMERICAN BIO MEDICA CORPORATION


                                            By:  /s/ Stan Cipkowski
                                                 --------------------------
                                                     Stan Cipkowski
                                                     President

Placement Agents:

Brean Murray & Co., Inc.
/s/ A. Brean Murray
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Its:  President and CEO

/s/David L. Jordon
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/s/ Barry Zelin
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Axiom Capital Management
/s/ Mark Martino
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Its: Managing Partner

/s/ Jeffrey Goldberg
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