Under the Securities Exchange Act of 1934
(Amendment No. 23)*

(Name of Issuer)

(Title of Class of Securities)

(CUSIP Number)

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

(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. o

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.

* 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) All shares of Common Stock held by Cascade Investment, L.L.C. (“Cascade”) may be deemed to be beneficially owned by William H. Gates III as the sole member of Cascade.

(2) Based on 347,238,344 shares of Common Stock outstanding as of October 22, 2015, as reported on the Issuer’s Form 10-Q filed on October 30, 2015.

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(1) All shares of Common Stock held by Cascade Investment, L.L.C. (“Cascade”) may be deemed to be beneficially owned by William H. Gates III as the sole member of Cascade.

(2) Based on 347,238,344 shares of Common Stock outstanding as of October 22, 2015, as reported on the Issuer’s Form 10-Q filed on October 30, 2015. 

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EXPLANATORY STATEMENT

This Amendment No. 23 to Schedule 13D (“Amendment”) amends and supplements the Schedule 13D previously filed by Cascade Investment, L.L.C. (“Cascade”), Bill & Melinda Gates Foundation Trust (the “Trust”), William H. Gates III (together with Cascade, the “Reporting Persons”) and Melinda French Gates with the Securities and Exchange Commission on July 21, 2008, as amended on August 1, 2008, August 18, 2008, September 22, 2008, December 16, 2008, January 15, 2009, January 29, 2009, February 9, 2009, February 23, 2009, March 3, 2009, October 30, 2009, November 5, 2010, August 18, 2011, December 9, 2011, May 4, 2012, May 25, 2012, August 3, 2012, November 19, 2012, June 12, 2014, July 1, 2014,  August 5, 2014, August 26, 2014, and September 19, 2014, relating to the Common Stock, par value $0.01 per share (the “Common Stock”) of Republic Services, Inc. (the “Issuer”).  This Amendment is being filed due an increase in the percentage of the Reporting Persons’ ownership resulting from a decrease in the Issuer’s outstanding shares of Common Stock and an increase in the number of shares beneficially owned by the Reporting Persons.  Since September 19, 2014, the Trust and Melinda French Gates have disposed of all of the shares of Common Stock that they beneficially owned and, as a result, have ceased to be reporting persons hereunder.

Item 3.           Source and Amount of Funds or Other Consideration

In May 2015, Cascade purchased 2,700,000 shares of Common Stock of the Issuer with its working capital for an aggregate purchase price of $108,212,887.58 (including commissions).

Item 5.           Interest in Securities of the Issuer

(a)     See items 11 and 13 of the cover pages to this Schedule 13D for the aggregate number of shares and percentage of Common Stock beneficially owned by each of the Reporting Persons.

(b)     See items 7 through 10 of the cover pages to this Schedule 13D for the number of shares and percentage of Common Stock beneficially owned by each of the Reporting Persons as to which there is sole power to vote or to direct the vote, shared power to vote or to direct the vote and sole or shared power to dispose or to direct the disposition.

(c)     None.

(d)    None.

(e)    Not applicable.

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SIGNATURE

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.

(1) This Amendment is being filed jointly by the Reporting Persons pursuant to the Joint Filing Agreement dated July 21, 2008 and included with the signature page to the Reporting Persons’ Schedule 13D filed on July 21, 2008, SEC File No. 005-54333, and incorporated by reference herein.

(2) Duly authorized under Special Limited Power of Attorney appointing Alan Heuberger attorney-in-fact, dated October 11, 2013, by and on behalf of Michael Larson, filed as Exhibit 99.1 to Amendment No. 9 to Cascade’s Schedule 13D with respect to Western Asset/Claymore Inflation-Linked Opportunities & Income Fund on December 11, 2013, SEC File No. 005-81261, and incorporated by reference herein.

(3) Duly authorized under Special Limited Power of Attorney appointing Alan Heuberger attorney-in-fact, dated August 12, 2008, by and on behalf of William H. Gates III, filed as Exhibit 99.2 to Amendment No. 1 to Cascade’s Schedule 13D with respect to Otter Tail Corporation on April 15, 2009, SEC File No. 005-06638, and incorporated by reference herein.

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