Fund Russell 1000® Growth Index

Sector Weightings: Defines what % of each sector this fund holdscompared to its benchmark listed here.

QTD YTD

Portfolio Attribution: Describes how fund manager sector and stockweighting decisions affected returns.

Sector Attribution Details: Sector Fund Weight Q T D Y T D

Communication Services 14.42 0.28 0.10

Consumer Discretionary 19.22 0.38 0.11

Consumer Staples 6.14 -0.29 -0.12

Energy 0.79 0.08 -0.05

Financials 4.68 -0.13 -0.44

Health Care 14.57 -0.14 -0.45

Industrials 6.83 -0.14 -0.30

Information Technology 31.16 -1.38 -3.25

Materials 0.22 0.11 0.10

Real Estate 0.01 0.25 0.07

Utilities 0.19 -0.02 0.01

Cash 0.73 -0.08 -0.37

Quarterly Portfolio Commentary:

Jason Marino, CFA, CAIA Investment DirectorInvestment Experience: 19 Years

HIGHLIGHTS• The domestic large-cap growth asset class outperformed the large-capvalue asset class for the fourth quarter in a row.• All sectors of the index delivered positive returns for the quarter, withhealth care and information technology leading the way.• Weak stock selection detracted from the Fund’s relative performance,mainly attributed to weakness in the information technology sector.• Sector allocation was essentially flat in the quarter as an underweightto the weak performing real estate sector offset an underweight to thestrong performing information technology sector.

Fund Objective: This Fund seeks growth of capital over the long term.

These materials and the platform of investments made available by MassMutual are offered without regard to the individualized needs of any plan, itsparticipants, or beneficiaries. These materials are not intended as impartial investment advice or to give advice in a fiduciary capacity to any plan.

NOT FDIC INSURED MAY LOSE VALUE NO BANK GUARANTEE

Quarterly Review

R5 SHARE CLASS TICKER: MBCSX

As of 12/31/2019

MassMutual Select Blue Chip Growth FundT. Rowe Price Associates, Inc. | Loomis Sayles & Company

Com

m. Services

Consumer Discr.

Consumer Staples

Energy

Financials

Health Care

Industrials

Information Tech.

Materials

Real Estate

Utilities

Cash

0

10

20

30

40

Percent of P

ortfolio

Percent of P

ortfolio

Com

m. Services

Consumer Discr.

Consumer Staples

Energy

Financials

Health Care

Industrials

Information Tech.

Materials

Real Estate

Utilities

Cash

-4.5

-3.0

-1.5

0.0

1.5

Value Added vs. Benchmark (%

)Value Added vs. Benchmark (%

)

Quarterly Portfolio Commentary:

The Russell 1000® Growth Index outperformed the Russell 1000® Value Index in the quarter as large-cap growth stocks continued to lead large-cap valuestocks in overall returns. Large-cap growth equities also outperformed their mid- and small-cap counterparts. All ten sectors delivered positive returns inthe period, with health care and information technology delivering the largest gains. As information technology and health care represent the largest twosectors, accounting for more than half of the index weight, their outperformance had significant impact on returns. The information technology sectormade the largest contribution to returns benefiting from strong price appreciation from both Microsoft and Apple, the two largest companies in the index.The health care sector delivered the second largest positive contribution as shares of health care providers and services, and biotechnology firms postedstrong share price gains. The troubled energy sector, the worst performing sector for the full year, delivered a respectable gain in the quarter as oil pricestrended higher in the quarter.

The Fund bounced back from its third quarter loss to post strong absolute returns for both the quarter and year. The Fund outperformed the peer groupfor the quarter, though trailed the benchmark for the period. Despite posting its second best calendar year return of the decade, the Fund lagged boththe benchmark and peer group for the year. For the calendar year period, an underweight allocation to Apple, the benchmark’s largest position, wasamong the largest relative detractors as the stock’s price posted very strong returns.

Weak stock selection was the primary detractor to relative returns for the quarter. The information technology sector was the largest relative detractor ona combination of an underweight allocation to the strong performing sector and weak stock selection within. Management’s underweight allocation toApple was again the largest individual relative detractor in the sector. A modest decline in the share price of Oracle, one of the top overall detractors toFund performance, also weighed on the sector. Although Oracle posted better-than-expected earnings for its fiscal second quarter, they reporteddisappointing year-over-year revenue and sales growth. Despite being an area of relative weakness, four of the Fund’s top seven contributors toperformance – Microsoft, Visa, NVIDIA Corp and Autodesk – came from the sector.

Strong stock selection within the consumer discretionary sector contributed to returns, and placed the sector as the top contributor to relative returns.Driving relative performance was Alibaba, which was also the Fund’s top contributor to returns, and not holding shares in Home Depot. Alibaba postedstrong share price returns as the company continues to execute on investor expectations and U.S.-China trade tensions eased in the quarter.

The Fund’s largest overweight allocations are to the consumer discretionary and communication services sectors, while the largest underweights are tothe information technology and industrials sectors.

TICKER: MBCSX Fund Inception: 6/1/2001Morningstar Category: Large Cap Growth

Average Annual Total Return

Q T D Y T D 1 Year 3 Year 5 Year 10 year

MassMutual Select Blue Chip Growth R5 9.48% 30.75% 30.75% 21.01% 14.96% 15.83%

Russell 1000® Growth Index 10.62% 36.39% 36.39% 20.49% 14.63% 15.22%

Category Average Return -- -- 31.90% 18.09% 12.10% 13.40%

Category Rank -- -- 63 23 12 8

# of Funds in Category -- -- 1,360 1,218 1,086 811

Performance shown is for class R5 shares. Gross expenses = 0.74%, Net expense = 0.74%. Max Sales charge for R5 is 0%Performance shown is past performance. Past performance does not guarantee future results . You can lose money, includingloss of pr incipal , by invest ing in this fund. Investors should careful ly consider investment objectives, r isks , charges andexpenses. This and other important information is contained in the fund prospectuses and summary prospectuses, which can beobtained from www.massmutualfunds.com and should be read careful ly before invest ing. A l ist of the Fund’s holdings can alsobe obtained from www.massmutualfunds.com. Current performance may be lower or higher than return data quoted herein. Formore current information, including month-end performance, please cal l 1-866-444-2601. You cannot invest directly in an index.Investment Risks - The Fund’s Princ ipa l R isks include- Cash Position Risk, Convertible Securities Risk, Equity Securities Risk, Foreign Investment Risk;Emerging Markets Risk; Currency Risk, Growth Company Risk, Large Company Risk, Liquidity Risk, Management Risk, Market Risk, Sector Risk, PreferredStock Risk, Smaller and Mid-Cap Company Risk, Valuation Risk. Please refer to the summary prospectus (a copy can be obtained by sending an email tofundinfo@massmutual.com) for more information on the specific risks.The Morningstar percenti le ranking is based on the fund’s total-return percenti le rank relat ive to al l funds that have the samecategory for the same t ime period. The highest (or most favorable) percentile rank is 1%, and the lowest (or least favorable) percentile rank is 100%.Morningstar total return includes both income and capital gains or losses and is not adjusted for sales charges. © 2019 Morningstar, Inc. All RightsReserved. The information contained herein: (1) is proprietary to Morningstar and/or its content providers; (2) may not be copied or distributed; and (3) isnot warranted to be accurate, complete or timely. Neither Morningstar nor its content providers are responsible for any damages or losses arising from anyuse of this information.

MassMutual Select Blue Chip Growth Fund

Quarter to Date:

Top 5 Contributors F u n dW e i g h t

AbsoluteReturn*

Portfol ioContr ibut ion

Alibaba Group Holding LtdADR 4.69 26.83 1.17

Facebook Inc A 5.93 15.26 0.86

Microsoft Corp 4.79 13.82 0.64

Amazon.com Inc 7.66 6.45 0.50

Visa Inc Class A 5.18 9.42 0.48

 

Top 5 Detractors F u n dW e i g h t

AbsoluteReturn*

Portfol ioContr ibut ion

Boeing Co 1.84 -13.89 -0.28

Yum Brands Inc 0.95 -10.82 -0.13

Danone SA ADR 1.21 -5.93 -0.08

Oracle Corp 2.17 -3.30 -0.07

Colgate-Palmolive Co 0.80 -5.75 -0.05

Year to Date:

Top 5 Contributors F u n dW e i g h t

AbsoluteReturn*

Portfol ioContr ibut ion

Facebook Inc A 5.51 56.57 2.57

Microsoft Corp 4.80 57.57 2.53

Alibaba Group Holding LtdADR 4.39 54.74 2.24

Visa Inc Class A 5.00 43.32 2.04

Amazon.com Inc 8.17 23.03 1.91

Top 5 Detractors F u n dW e i g h t

AbsoluteReturn*

Portfol ioContr ibut ion

Tesla Inc 0.09 -25.59 -0.10

Humana Inc 0.13 -9.52 -0.05

TD Ameritrade Holding Corp 0.60 4.08 -0.04

Dollar Tree Inc 0.08 -12.96 -0.04

Concho Resources Inc 0.05 -28.22 -0.04

RS9093b RS-45343-06

Portfolio Holdings:

 Fund Weightings are shown as an average for the time period.*Absolute Return is the return that an asset achieves over a certain period of time. This measure looks at the appreciation or depreciation (expressed as apercentage) that a holding achieves over a given period of time.For a complete listing of fund holdings, visit massmutualfunds.com or please call 1-866-444-2601. The mention of individual stocks and other securities inthis document does not constitute investment advice.

© 2020 Massachusetts Mutual Life Insurance Company (MassMutual®), Springfield, MA. All rights reserved. www.MassMutual.com Principal Underwriter:MML Distributors, LLC. (MMLD) Member FINRA and SIPC (www.FINRA.org and www.SIPC.org) MMLD is a subsidiary of Massachusetts Mutual LifeInsurance Company, 100 Bright Meadow Blvd., Enfield, CT 06082. Investment advisory services provided to the Funds by MML Investment Advisers, LLC.

MassMutual Select Blue Chip Growth Fund

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