MFS New Discovery Fund

MFS SERIES TRUST I · 9 share classes

Actively managed U.S. equity fund
One fund, 9 share classes:MNDAXMNDJXMNDBXMNDCXMNDIXMNDGXMNDRXMNDHXMNDKX
$2.14B NAV
119 positions · as of 2026-05-31 · filed 2026-07-27

Fund classification

Classified from what the fund holds · as of 2026 Q2

MFS New Discovery Fund is an actively managed U.S. equity fund.

Asset class
Equity
Region
United States
Management
Actively managed
Fund type
Open-end fund

Fund profile

As filed in the prospectus · 2025 Q4

The funds investment objective is to seek capital appreciation.

Strategy · summarised

The fund invests primarily in equity securities of small-capitalization companies selected through fundamental analysis for above-average earnings growth potential, with MFS employing a bottom-up approach that may also use quantitative screening. The fund may invest significantly in foreign securities and concentrate a substantial portion of assets in a single industry or sector. Because the fund's returns depend on the success of individual security selections, performance will diverge from any benchmark if those selections underperform or outperform.

Expenses
0.85% 1.96%across 9 share classes
Share classGrossNet
MNDAX1.28%1.21%
MNDJX1.03%0.96%
MNDBX2.03%1.96%
MNDCX2.03%1.96%
MNDIX1.03%0.96%
MNDGX2.03%1.96%
MNDRX1.53%1.46%
MNDHX1.28%1.21%
MNDKX0.91%0.85%

Net is what a holder pays after the adviser's contractual waiver; gross is before it. A waiver can expire.

Portfolio turnover 68.00% · as of 2025 Q4

Allocation

Asset groups · long / short shown separately, never netted · 2026 Q2

104.24%
of net assets
Stocks100.03%
Cash & short-term4.21%

Derivatives are shown at market value, not notional exposure.

Sector allocation

The same holdings as Allocation above, grouped by market sector instead of asset type · as of 2026 Q2

100%
of net assets
Health Care24.4%
Industrials19.9%
Information Technology17.1%
International7.4%
9 smaller31.2%

Government, Securitized and Cash are non-corporate buckets; International is foreign holdings we don’t sector-classify, and Other is the residual (held funds, unresolved names).

Latest quarter

What changed since the fund's previous filing

2026Q2 vs 2026Q1: 28 new18 exited

Largest new: Finning International Inc, DCI, MMSI, IONQ, TKR, SSRM, DGII, OII

Largest exited: CR, HLNE, Ascendis Pharma A/S, ALKT, Genius Sports Ltd, WGS, ALGN, NTSK

Return profile

Chart:

Total return as filed — price change plus distributions reinvested · trailing figures to Apr 2026

Share class1-year3-year5-yearVolWorst fall
+30.48%+37.65%-1.65%13.94%-15.76%
+30.82%+38.68%-0.42%13.94%-15.72%
+29.55%+34.54%-5.29%13.95%-15.92%
+29.53%+34.48%-5.29%13.94%-15.91%
+30.84%+38.63%-0.41%13.95%-15.73%
+29.56%+34.54%-5.27%13.98%-15.93%
+30.21%+36.60%-2.83%13.98%-15.77%
+30.53%+37.64%-1.62%13.98%-15.76%
+31.01%+39.19%+0.18%13.98%-15.67%

These classes hold the same portfolio, so the 5.47pp spread over 5 years is the cost difference between them — roughly 1.09pp a year — not a difference in what they own.

Cumulative return· Jun 2023 – Apr 2026

May 2026 has been filed since the trailing figures were struck, so it is not in the table above or the curve — every figure here shares one cut-off, which is what makes them comparable with other funds.

Holdings

By % of NAV · equity positions carry filed share counts · every resolvable issuer links to its company page

Issuer%NAVValue
JP Morgan US Government Money Market FundMGMXX4.21%$90.19M
MFS Institutional Money Market Portfolio3.99%$85.38M
Advanced Energy Industries IncAEIS2.34%$50.18M
Littelfuse IncLFUS2.19%$46.90M
TTM Technologies IncTTMI1.99%$42.63M
Element Solutions IncESI1.93%$41.30M
Ligand Pharmaceuticals IncLGND1.91%$40.80M
CACI International IncCACI1.87%$40.10M
Leonardo DRS IncDRS1.76%$37.78M
Bloom Energy CorpBE1.67%$35.83M
Showing 10 of 119Sign in to see more

Reported price is the fund's own reported value divided by its own reported shares at 2026-05-31 — not a live quote, and not what the fund paid.

Top 10 positions are 23.87% of net assets, top 25 44.75%, across 119 issuers.

See more of this fund's book

More positions with filed share counts, and the quarter-over-quarter change list rather than the largest few — free with an account, no card required.

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