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Boston Common Asset Management, LLC — 13F Holdings & Portfolio

CIK 1409427 · latest 13F-HR filed 2026-10-13

Backtest portfolio

Boston Common Asset Management, LLC manages $1.72B in 13F-reported U.S. long-equity assets across 181 reported positions as of its 2026-09-30 13F-HR filing. Its largest disclosed positions are TSM (6.74%), MSFT (4.99%), NVDA (4.78%). Quarter over quarter (versus its 2026-06-30 filing) the fund opened 8 new positions and exited 13; 79 existing positions rose in reported value and 54 fell.

AUM is the long-equity portion reported on Form 13F-HR. Excludes short positions, cash, foreign holdings, and non-13F assets. For informational purposes only — not investment advice.

Loading holdings…
AUM
$1.72B

Long-equity book

Holdings
181

Distinct positions

Period
2026-09-30

Filed 2026-10-13

Q/Q Activity
+8 / −13 / ↑79 / ↓54

vs 2026-06-30

Portfolio charts

Latest quarter's book, what changed, and how the portfolio has evolved across filings.

Portfolio map

Q3 26
TSM6.7% · -4%MSFT5.0% · +6%NVDA4.8% · -1%AAPL4.5% · +4%GOOGL3.0% · +4%AVGO2.5% · +7%GOOG2.1% · -3%V1.9% · +3%MRK1.8% · +8%MU1.7% · +20%MS1.7% · -2%LLY1.6% · +7%DGX1.4% · +7%WAB1.2% · +3%CL1.2% · +7%HUBB1.2% · +7%SPOT1.2% · -16%NUSC1.2% · -2%NFLX1.1% · -11%HPE1.1% · +539%RHHBY1.1% · +17%VRT1.1% · +2%AWK1.0% · +6%BNY1.0% · newCB0.9% · -2%VZ0.9% · +12%XYL0.9% · +5%EW0.9% · +8%GILD0.9% · +17%TJX0.8% · -0%PANW0.8% · -17%SCHW0.8% · +21%ADI0.8% · -10%FITB0.8% · +13%AMAT0.8% · -47%TMUS0.8% · +8%MET0.8% · +30%ECL0.8% · -0%EMR0.8% · +9%HASI0.7% · +6%HDB0.7% · +9%WM0.7% · +9%EBAY0.7% · +14%CBRE0.7% · +6%DHR0.7% · +11%VRTX0.7% · +19%MUFG0.7% · +2%BAC0.7% · -1%CME0.7% · +12%ASML0.6% · +37%COST0.6% · -1%SAP0.6% · +2%ITUB0.6% · -0%CMI0.6% · +8%AMD0.6% · -1%UL0.5% · -0%RL0.5% · -1%TT0.5% · +7%SFM0.5% · +12%SCBFF0.5% · new

Box size = position value; colour = change in share count vs the prior quarter (green added, red trimmed, blue new). Rows split across managers or share classes are combined. Click a box for the stock.

Sector mix

% of 13F value

Sectors from each company's SIC code; funds and ETFs grouped separately.

Biggest buys and sells

Q2 26 → Q3 26

Estimated from the change in shares held × the quarter-end price, so price moves alone don't count as buying. New and exited positions are included.

13F assets and positions

4 quarters

Total reported 13F value (bars) and number of positions (line) each quarter. Value changes include market moves.

Top positions over time

reported value

The eight largest current positions, valued at each quarter end.

Concentration

top 10 = 34%

Cumulative share of the portfolio held in the largest N positions.

Firm Profile & Key People

As of the firm’s regulatory filing dated Jul 6, 2026.

Assets Under Management
$4.17B
Discretionary
$4.17B
Employees
39
Accounts
343
Address
200 STATE STREET, 7TH FLOOR
BOSTON, MA 02109
Phone
(617) 720-5557
Website
Name Title / Status Ownership Type
AIYER, GEETA, BHIDE ControlMEMBER
since Sep 2002
10–25%Individual
Streur, John, H ControlMEMBER
since Oct 2025
10–25%Individual
ZALOSH, MATTHEW, ADAM ControlMEMBER
since Apr 2009
10–25%Individual
Abichandani, PraveenMEMBER
since Apr 2009
5–10%Individual
BC ACQUISITION, LLC.MEMBER
since Feb 2021
10–25%Domestic Entity
COMPERE, LAUREN, MARIEMEMBER
since Apr 2009
5–10%Individual
EISNOR, KRISTINA, INGRIDCHIEF COMPLIANCE OFFICER
since Jan 2013
10–25%Individual
RYAN, KIMBERLY, ELIZABETHMEMBER
since Jun 2026
5–10%Individual
Su, LizMEMBER
since Mar 2023
5–10%Individual
AFFILIATED MANAGERS GROUP, INC. Control
Indirect owner via BC ACQUISITION, LLC.
MEMBER
since Dec 2020
75% or moreDomestic Entity
Ownership & leadership changes · 15 filings with changes since Mar 29, 2012

From the firm’s regulatory filings, newest first. Dates are filing dates: a filing that no longer lists someone does not say when they left.

Jul 6, 2026 filing
  • AddedRYAN, KIMBERLY, ELIZABETH · MEMBER · 5–10%
Feb 10, 2026 filing
  • ChangedStreur, John, H · ownership 5–10% → 10–25%
Oct 16, 2025 filing
  • No longer listedBiemans, Corne · MEMBER · 5–10% · listed since Oct 2016
  • AddedStreur, John, H · MEMBER · 5–10% · control person
  • ChangedSu, Liz · title PORTFOLIO MANAGER → MEMBER; ownership Less than 5% → 5–10%
Jul 3, 2025 filing
  • No longer listedSPADY, NANCY, GROSSMAN · MEMBER · 5–10% · control person · listed since Apr 2009
  • ChangedEISNOR, KRISTINA, INGRID · ownership Less than 5% → 10–25%
Mar 31, 2025 filing
  • No longer listedMCDONALD, ALLYSON, MORGAN · MEMBER · 5–10% · control person · listed since Jan 2020
  • ChangedSu, Liz · ownership 5–10% → Less than 5%
Feb 12, 2024 filing
  • ChangedMCDONALD, ALLYSON, MORGAN · title CHIEF EXECUTIVE OFFICER → MEMBER
Apr 28, 2023 filing
  • AddedSu, Liz · PORTFOLIO MANAGER · 5–10%
Mar 30, 2022 filing
  • No longer listedHEIM, STEVEN, F. · MEMBER · Less than 5% · listed since Apr 2009
Mar 31, 2021 filing
  • No longer listedROSEMONT PARTNERS III, LP · MEMBER · 10–25% · listed since Oct 2016
Feb 10, 2021 filing
  • No longer listedROSEMONT INVESTMENT PARTNERS III, LLC · GP · General partner, trustee or manager · indirect via ROSEMONT PARTNERS III, LP · control person · listed since Oct 2010
  • AddedAFFILIATED MANAGERS GROUP, INC. · MEMBER · 75% or more · indirect via BC ACQUISITION, LLC. · control person
  • AddedBC ACQUISITION, LLC. · MEMBER · 10–25%
Older changes (6 more filings)
Jun 29, 2020 filing
  • ChangedHEIM, STEVEN, F. · ownership 5–10% → Less than 5%
Mar 24, 2020 filing
  • AddedMCDONALD, ALLYSON, MORGAN · CHIEF EXECUTIVE OFFICER · 5–10% · control person
Mar 30, 2017 filing
  • AddedROSEMONT INVESTMENT PARTNERS III, LLC · GP · General partner, trustee or manager · indirect via ROSEMONT PARTNERS III, LP · control person
Jan 13, 2017 filing
  • AddedAbichandani, Praveen · MEMBER · 5–10%
  • AddedBiemans, Corne · MEMBER · 5–10%
  • AddedROSEMONT PARTNERS III, LP · MEMBER · 10–25%
  • ChangedAIYER, GEETA, BHIDE · ownership 50–75% → 10–25%
  • ChangedSPADY, NANCY, GROSSMAN · ownership Less than 5% → 5–10%
  • ChangedZALOSH, MATTHEW, ADAM · ownership 5–10% → 10–25%
Jan 11, 2013 filing
  • No longer listedPOVERMAN, KATE · CHIEF COMPLIANCE OFFICER · Less than 5% · listed since Jul 2008
  • AddedEISNOR, KRISTINA, INGRID · CHIEF COMPLIANCE OFFICER · Less than 5%
Mar 29, 2012 filing (earliest on record)
  • ListedAIYER, GEETA, BHIDE · MEMBER · 50–75% · control person
  • ListedCOMPERE, LAUREN, MARIE · MEMBER · 5–10%
  • ListedHEIM, STEVEN, F. · MEMBER · 5–10%
  • ListedPOVERMAN, KATE · CHIEF COMPLIANCE OFFICER · Less than 5%
  • ListedSPADY, NANCY, GROSSMAN · MEMBER · Less than 5% · control person
  • ListedZALOSH, MATTHEW, ADAM · MEMBER · 5–10% · control person

Quarter-over-quarter changes

Changes in reported position value vs the prior 13F, so price moves count too, not just shares bought or sold.

Boston Common Asset Management, LLC Holdings (2026-09-30)

Rows tagged Call or Put are options positions, not stock. Per SEC Form 13F-HR, Value shows the notional value of the underlying (shares covered × underlying price), not the option premium. Shares is the number of underlying shares covered (divide by 100 for contract count).

# Issuer Symbol CUSIP Value Weight Shares Type
1 Taiwan Semiconductor Manufacturing Co., Ltd. TSM 874039100 $116.2M 6.74% 254,658 SH
2 Microsoft Corp. MSFT 594918104 $86.0M 4.99% 167,723 SH
3 NVIDIA Corp. NVDA 67066G104 $82.4M 4.78% 360,821 SH
4 Apple Inc. AAPL 037833100 $77.8M 4.51% 233,653 SH
5 Alphabet Inc. GOOGL 02079K305 $51.0M 2.96% 148,215 SH
6 Broadcom Inc AVGO 11135F101 $42.7M 2.47% 121,497 SH
7 Alphabet Inc. GOOG 02079K107 $36.3M 2.10% 106,431 SH
8 Visa Inc V 92826C839 $32.9M 1.91% 91,514 SH
9 Merck & Co., Inc MRK 58933Y105 $31.2M 1.81% 214,998 SH
10 Micron Technology Inc. MU 595112103 $30.0M 1.74% 28,208 SH
11 Morgan Stanley MS 617446448 $29.1M 1.69% 154,972 SH
12 Eli Lilly & Co. LLY 532457108 $28.0M 1.62% 24,195 SH
13 Quest Diagnostics Incorporated DGX 74834L100 $23.8M 1.38% 102,025 SH
14 Wabtec Corp WAB 929740108 $21.5M 1.25% 74,922 SH
15 Colgate-Palmolive Co. CL 194162103 $21.1M 1.22% 247,061 SH
16 Hubbell Incorporated HUBB 443510607 $21.0M 1.22% 46,350 SH
17 Spotify Technology S.A. SPOT L8681T102 $20.5M 1.19% 41,963 SH
18 NuShares ETF Trust NUSC 67092P607 $19.9M 1.15% 409,886 SH
19 Netflix, Inc. NFLX 64110L106 $19.7M 1.14% 282,732 SH
20 Hewlett Packard Enterprise Co. HPE 42824C109 $18.7M 1.08% 292,579 SH
21 Roche Holding AG RHHBY 771195104 $18.2M 1.05% 350,571 SH
22 Vertiv Holdings Co VRT 92537N108 $18.1M 1.05% 75,065 SH
23 American Water Works Company, Inc. AWK 030420103 $17.4M 1.01% 134,519 SH
24 The Bank of New York Mellon Corp. BNY 064058100 $17.0M 0.99% 117,603 SH
25 Chubb Ltd. CB H1467J104 $16.3M 0.95% 50,193 SH
26 Verizon Communications Inc. VZ 92343V104 $15.8M 0.92% 344,081 SH
27 Xylem, Inc. XYL 98419M100 $15.2M 0.88% 150,056 SH
28 Edwards Lifesciences Corporation EW 28176E108 $15.0M 0.87% 173,996 SH
29 Gilead Sciences Inc. GILD 375558103 $14.8M 0.86% 99,047 SH
30 The TJX Companies Inc. TJX 872540109 $14.3M 0.83% 108,085 SH
31 Palo Alto Networks Inc PANW 697435105 $14.1M 0.82% 35,393 SH
32 The Charles Schwab Corporation SCHW 808513105 $13.9M 0.80% 141,980 SH
33 Analog Devices Inc. ADI 032654105 $13.7M 0.79% 34,458 SH
34 Fifth Third Bancorp FITB 316773100 $13.5M 0.78% 266,083 SH
35 Applied Materials Inc. AMAT 038222105 $13.4M 0.78% 26,238 SH
36 T-Mobile US Inc TMUS 872590104 $13.3M 0.77% 81,585 SH
37 MetLife Inc. MET 59156R108 $13.3M 0.77% 140,761 SH
38 Ecolab Inc. ECL 278865100 $13.2M 0.77% 48,177 SH
39 Emerson Electric Co. EMR 291011104 $13.2M 0.77% 85,188 SH
40 HA Sustainable Infrastructure Capital Inc HASI 41068X100 $12.9M 0.75% 358,948 SH
41 HDFC Bank Ltd. HDB 40415F101 $12.5M 0.73% 561,298 SH
42 Waste Management, Inc. WM 94106L109 $12.5M 0.72% 61,131 SH
43 eBay Inc. EBAY 278642103 $12.4M 0.72% 116,985 SH
44 CBRE Group Inc. CBRE 12504L109 $12.3M 0.71% 95,905 SH
45 Danaher Corporation DHR 235851102 $12.1M 0.70% 54,806 SH
46 Vertex Pharmaceuticals Incorporated VRTX 92532F100 $12.1M 0.70% 23,215 SH
47 Mitsubishi UFJ Financial Group Inc. MUFG 606822104 $11.5M 0.67% 497,504 SH
48 Bank of America Corp. BAC 060505104 $11.3M 0.66% 207,821 SH
49 CME Group Inc. CME 12572Q105 $11.2M 0.65% 42,877 SH
50 ASML Holding N.V. ASML N07059210 $10.7M 0.62% 5,898 SH
Filing History
Period Filed AUM Holdings Accession
2026-09-30 2026-10-13 $1.72B 181 0001409427-26-000014
2026-06-30 2026-07-21 $1.69B 186 0001409427-26-000008
2026-03-31 2026-05-07 $1.55B 186 0001409427-26-000004
2025-12-31 2026-05-07 $1.66B 195 0001409427-26-000006
Filer Information
Address
200 STATE ST, 7TH FLOOR
BOSTON, MA 02109
Phone
(617) 720-5557
Filing Manager
Boston Common Asset Management, LLC
BOSTON, MA
Signatory
Kristina Eisnor
Chief Compliance Officer