Marsh & McLennan Indenture Agreements

Seventeenth Supplemental Indenture, dated September 11, 2023, between Marsh & McLennan Companies, Inc. and The Bank of New York Mellon, as trustee (Filed With SEC on September 11, 2023)

Sixteenth Supplemental Indenture, dated March 9, 2023, between Marsh & McLennan Companies, Inc. and The Bank of New York Mellon, as trustee (Filed With SEC on March 9, 2023)

Fifteenth Supplemental Indenture, dated October 31, 2022, between Marsh & McLennan Companies, Inc. and The Bank of New York Mellon, as trustee (Filed With SEC on October 31, 2022)

Fourteenth Supplemental Indenture, dated December 8, 2021, between Marsh & McLennan Companies, Inc. and The Bank of New York Mellon, as trustee (Filed With SEC on December 9, 2021)

Thirteenth Supplemental Indenture, dated May 7, 2020, between Marsh & McLennan Companies, Inc. and The Bank of New York Mellon, as trustee (Filed With SEC on May 7, 2020)

Twelfth Supplemental Indenture, dated March 21, 2019, between Marsh & McLennan Companies, Inc. and The Bank of New York Mellon, as trustee (Filed With SEC on March 21, 2019)

Eleventh Supplemental Indenture, dated January 15, 2019, between Marsh & McLennan Companies, Inc. and The Bank of New York Mellon, as trustee (Filed With SEC on January 15, 2019)

Tenth Supplemental Indenture, dated as of March 1, 2018, between Marsh & McLennan Companies, Inc. and The Bank of New York Mellon, as trustee (Filed With SEC on April 27, 2018)

Form of Tenth Supplemental Indenture between Marsh & McLennan Companies, Inc. and The Bank of New York Mellon, as trustee (Filed With SEC on March 1, 2018)

MARSH & McLENNAN COMPANIES, INC., Issuer, and The Bank of New York Mellon, Trustee ____________________ NINTH SUPPLEMENTAL INDENTURE Dated as of January 12, 2017... (Filed With SEC on February 24, 2017)

MARSH & McLENNAN COMPANIES, INC., Issuer, and The Bank of New York Mellon, Trustee NINTHSUPPLEMENTAL INDENTURE Dated as of January 12, 2017 $500,000,000 aggregate principal amount... (Filed With SEC on January 12, 2017)

MARSH & McLENNAN COMPANIES, INC., Issuer, and The Bank of New York Mellon, Trustee ____________________ EIGHTH SUPPLEMENTAL INDENTURE Dated as of March 14, 2016... (Filed With SEC on May 2, 2016)

MARSH & McLENNAN COMPANIES, INC., Issuer, and The Bank of New York Mellon, Trustee EIGHTHSUPPLEMENTAL INDENTURE Dated as of March 14, 2016 $350,000,000aggregate principal amount... (Filed With SEC on March 14, 2016)

MARSH & McLENNAN COMPANIES, INC., Issuer, and The Bank of New York Mellon, Trustee SEVENTHSUPPLEMENTAL INDENTURE Dated as of September 14, 2015 $600,000,000 aggregate principal... (Filed With SEC on September 14, 2015)

Exhibit 4.1 MARSH & McLENNAN COMPANIES, INC., Issuer, and The Bank of New York Mellon, Trustee ____________________ SIXTH SUPPLEMENTAL INDENTURE Dated as of March 6, 2015... (Filed With SEC on May 4, 2015)

MARSH & McLENNAN COMPANIES, INC., Issuer, and The Bank of New York Mellon, Trustee SIXTHSUPPLEMENTAL INDENTURE Dated as of March 6, 2015 $500,000,000aggregate principal amount of... (Filed With SEC on March 6, 2015)

MARSH & McLENNAN COMPANIES, INC., Issuer, and The Bank of New York Mellon, Trustee FIFTHSUPPLEMENTAL INDENTURE Dated as of September 10, 2014 $300,000,000 aggregate principal... (Filed With SEC on September 10, 2014)

MARSH & McLENNAN COMPANIES, INC., Issuer, and The Bank of New York Mellon, Trustee FOURTHSUPPLEMENTAL INDENTURE Dated as of May 30, 2014 $600,000,000aggregate principal amount of... (Filed With SEC on May 30, 2014)

MARSH & McLENNAN COMPANIES, INC., Issuer, and The Bank of New York Mellon, Trustee THIRDSUPPLEMENTAL INDENTURE Dated as of September 27, 2013 $250,000,000 aggregate principal... (Filed With SEC on September 27, 2013)

MARSH & McLENNAN COMPANIES, INC., Issuer, and The Bank of New York Mellon, Trustee ____________________ SECOND SUPPLEMENTAL INDENTURE Dated as of March 12, 2012... (Filed With SEC on March 9, 2012)

MARSH & McLENNANCOMPANIES INC., Company AND THE BANK OF NEW YORK MELLON, Trustee INDENTURE Dated as of July 15, 2011 Senior DebtSecurities CROSS-REFERENCE TABLE* (Filed With SEC on August 5, 2011)

MARSH & McLENNANCOMPANIES INC., Issuer, and The Bank of New York Mellon, Trustee FIRSTSUPPLEMENTAL INDENTURE Dated as of July 15, 2011 $500,000,000 aggregate principal amount of... (Filed With SEC on August 5, 2011)

MARSH & McLENNANCOMPANIES INC., Issuer, and The Bank of New York Mellon, Trustee FIRSTSUPPLEMENTAL INDENTURE Dated as of July 15, 2011 $500,000,000 aggregate principal amount of... (Filed With SEC on July 15, 2011)