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 Rule 13d-1(e), Rule 13d-1(f) or Rule 13d-1(g), check the following box. [ ]

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* 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).

(1) Excludes cash-settled swaps disclosed in Item 5 representing economic exposure comparable to 1,495,999 additional shares of Common Stock (as defined below), which if aggregated with such beneficially owned shares, represent an aggregate economic interest in 2,103,999 shares representing 2.3% of the outstanding shares.

(1) Excludes cash-settled swaps disclosed in Item 5 representing economic exposure comparable to 3,179,001 additional shares of Common Stock (as defined below), which if aggregated with such beneficially owned shares, represent an aggregate economic interest in 4,471,001 shares representing of 4.8% of the outstanding shares.

(1) Excludes cash-settled swaps disclosed in Item 5 representing economic exposure comparable to 3,179,001 additional shares of Common Stock (as defined below), which if aggregated with such beneficially owned shares, represent an aggregate economic interest in 4,471,001 shares representing of 4.8% of the outstanding shares.

(a)-(c) This statement is being filed by Elliott Associates, L.P., a Delaware limited partnership, and its wholly-owned subsidiaries (collectively, "Elliott" or "we"), Elliott International, L.P., a Cayman Islands limited partnership ("Elliott International"), and Elliott International Capital Advisors Inc., a Delaware corporation ("EICA" and collectively with Elliott and Elliott International, the "Reporting Persons"). Paul E. Singer ("Singer"), Elliott Capital Advisors, L.P., a Delaware limited partnership ("Capital Advisors"), which is controlled by Singer, and Elliott Special GP, LLC, a Delaware limited liability company ("Special GP"), which is controlled by Singer, are the general partners of Elliott.  Hambledon, Inc., a Cayman Islands corporation ("Hambledon"), which is also controlled by Singer, is the sole general partner of Elliott International. EICA is the investment manager for Elliott International.  EICA expressly disclaims equitable ownership of and pecuniary interest in any shares of Common Stock.

ELLIOTT

The business address of Elliott is 40 West 57th Street, New York, New York 10019.

The principal business of Elliott is to purchase, sell, trade and invest in securities.

SINGER

Singer's business address is 40 West 57th Street, New York, New York 10019.

Singer's principal business is to serve as a general partner of Elliott and Capital Advisors, as the president of EICA, and as a managing member of Special GP.

CAPITAL ADVISORS

The business address of Capital Advisors is 40 West 57th Street, New York, New York 10019.

The principal business of Capital Advisors is the furnishing of investment advisory services.  Capital Advisors also serves as a managing member of Special GP.

The names, business addresses, and present principal occupation or employment of the general partners of Capital Advisors are as follows:

The name, business address, and present principal occupation or employment of the sole director and executive officer of Braxton Associates, Inc. are as follows:

ELLIOTT SPECIAL GP, LLC

The business address of Special GP is 40 West 57th Street, New York, New York 10019.

The principal business of Special GP is serving as a general partner of Elliott.

The names, business address, and present principal occupation or employment of the managing members of Special GP are as follows:

ELLIOTT INTERNATIONAL

The business address of Elliott International is c/o Maples & Calder, P.O. Box 309, Ugland House, South Church Street, George Town, Cayman Islands, British West Indies.

The principal business of Elliott International is to purchase, sell, trade and invest in securities.

The name, business address, and present principal occupation or employment of the general partner of Elliott International is as follows:

HAMBLEDON

The name, business address, and present principal occupation or employment of the sole director and executive officer of Hambledon are as follows:

EICA

The business address of EICA is 40 West 57th Street New York, New York 10019.

The principal business of EICA is to act as investment manager for Elliott International.

The name, business address, and present principal occupation or employment of the sole director and executive officer of EICA is as follows:

(d) and (e) During the last five years, none of the persons or entities listed above  has been (i) convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors); or (ii) a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

(f) Singer is a citizen of the United States of America.

(a)       As of the date hereof, Elliott, Elliott International and EICA collectively have combined economic exposure in the Issuer of approximately 7.0% of the shares of Common Stock outstanding.

The aggregate percentage of Common Stock reported owned by each person named herein is based upon 93,655,243 shares of Common Stock outstanding, which is the total number of shares of Common Stock outstanding as of October 27, 2017 as reported in the Issuer's Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2017, filed with the Securities and Exchange Commission (the "SEC") on November 1, 2017.

As of the date hereof, Elliott itself and through The Liverpool Limited Partnership, a Bermuda limited partnership and a wholly-owned subsidiary of Elliott ("Liverpool") beneficially owned 608,000 shares of Common Stock, constituting 0.7% of the shares of Common Stock outstanding.

As of the date hereof, Elliott International beneficially owned 1,292,000 shares of Common Stock, constituting 1.4% of the shares of Common Stock outstanding. EICA, as the investment manager of Elliott International may be deemed to beneficially own the 1,292,000 shares of Common Stock beneficially owned by Elliott International, constituting 1.4% of the shares of Common Stock outstanding.

Collectively, Elliott, Elliott International and EICA beneficially own 1,900,000 shares of Common Stock, constituting approximately 2.0% of the shares of Common Stock outstanding.

Collectively, Elliott, Elliott International and EICA have economic exposure comparable to approximately 5.0% of the shares of Common Stock outstanding pursuant to the Derivative Agreements, as disclosed in Item 6.

(b)       Elliott has the power to vote or direct the vote of, and to dispose or direct the disposition of the shares of Common Stock owned directly by it.

Elliott International has the shared power with EICA to vote or direct the vote of, and to dispose or direct the disposition of, the shares of Common Stock owned directly by Elliott International. Information regarding each of Elliott International and EICA is set forth in Item 2 of this Schedule 13D and is expressly incorporated by reference herein.

(c)       The transactions effected by the Reporting Persons during the past 60 days are set forth on Schedule 1 attached hereto.

(d)       No person other than Elliott has the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the shares of Common Stock beneficially owned by Elliott.

No person other than Elliott International and EICA has the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the shares of Common Stock beneficially owned by Elliott International and EICA.

(e)       Not applicable.

Elliott, through Liverpool, and Elliott International have entered into notional principal amount derivative agreements (the "Derivative Agreements") in the form of cash settled swaps with respect to 1,495,999 and 3,179,001 shares of Common Stock of the Issuer, respectively (representing economic exposure comparable to 1.6% and 3.4% of the shares of Common Stock of the Issuer, respectively). Collectively, the Derivative Agreements held by the Reporting Persons represent economic exposure comparable to an interest in approximately 5.0% of the shares of Common Stock. The Derivative Agreements provide Elliott and Elliott International with economic results that are comparable to the economic results of ownership but do not provide them with the power to vote or direct the voting or dispose of or direct the disposition of the shares that are referenced in the Derivative Agreements (such shares, the "Subject Shares"). The Reporting Persons disclaim beneficial ownership in the Subject Shares. The counterparties to the Derivative Agreements are unaffiliated third party financial institutions.

On November 16, 2017 Elliott, Elliott International and EICA entered into a Joint Filing Agreement (the "Joint Filing Agreement") in which the parties 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. The Joint Filing Agreement is attached as Exhibit 99.1 hereto and is incorporated herein by reference.

Except as described above in this Item 6, none of the Reporting Persons has any contracts, arrangements, understandings or relationships with respect to the securities of the Issuer.

SIGNATURES

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

DATE: November 16, 2017

Exhibit 99.1

JOINT FILING AGREEMENT

The undersigned hereby agree that the statement on Schedule 13D with respect to the Common Stock of MEDNAX, Inc. dated November 16, 2017, and any further amendments thereto signed by each of the undersigned shall be, filed on behalf of each of the undersigned pursuant to and in accordance with the provisions of Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended.

DATE: November 16, 2017

SCHEDULE 1

Transactions of the Reporting Persons Effected During the Past 60 Days

The following transactions were effected by Elliott Associates, L.P. in the Common Stock during the past 60 days:

The following transactions were effected by Elliott Associates, L.P. (through Liverpool) in the Common Stock during the past 60 days:

The following transactions were effected by Elliott International, L.P. in the Common Stock during the past 60 days: