MAIRS & POWER INC ECL — Ecolab Inc COM

Ownership history in MAIRS & POWER INC  ·  108 quarters on record

AI Ownership Summary

MAIRS & POWER INC reported Ecolab Inc COM (ECL) in 108 quarterly 13F filings from 2023 Q4 through 2025 Q4. Peak portfolio weight reached 2.56% in 2023 Q4. The latest visible filing shows ECL at 1.95% of the fund.

This page tracks quarterly shares, estimated market value, portfolio weight, filing dates, and disclosure-aligned stock prices directly from SEC EDGAR 13F filings. Older history is available after unlock; the visible window still shows the most recent pattern.

What this ECL ownership page tells you

This page is designed to answer the real investor question behind a 13F filing: how meaningful was MAIRS & POWER INC's position in Ecolab Inc COM, and how did that conviction change over time? You can read the holding window, peak weight, latest reported size, disclosure timing, and quarter-by-quarter changes without piecing the story together from raw SEC rows.

Freshest filing
Latest Reported Filing
2025 Q4

ECL was reported at 1.95% of portfolio in the most recent visible filing.

High-water mark
Peak Conviction
2.56% in 2023 Q4

Peak weight helps separate a token disclosure from a real conviction holding the fund genuinely cared about.

Time in book
Holding Window
2023 Q4 to 2025 Q4

Longer holding windows often tell a very different story from short-lived tactical trades or one-quarter experiments.

Decision context
Why It Matters
Position size beats headlines

Knowing that a fund owned a stock is useful. Knowing whether it was a 0.20% placeholder or a true high-conviction position is where the signal actually starts.

ECL stock page MAIRS & POWER INC fund profile MAIRS & POWER INC full holdings
How MAIRS & POWER INC held ECL — position size vs. price
% of Fund (quarterly)    ECL price (quarter-end, indexed to 100)    SPY (indexed to 100)    QQQ (indexed to 100)
📋 Quarterly Holdings History 9 quarters  ▾
Quarter Action Sold % After 3M Timing Shares Change Chg % % of Fund Mkt Value Filed Price (Filed)
2025 Q4 REDUCED — — — 770,571 -6,458 -0.8% 1.95% $202.3M 2026-02-14 (Est.) $298.37
2025 Q3 REDUCED — — — 777,029 -11,900 -1.5% 2.00% $212.8M 2025-11-14 $257.17
2025 Q2 ADDED — — — 788,929 +15,743 +2.0% 2.10% $212.6M 2025-08-14 $277.78
2025 Q1 REDUCED — — — 773,186 -10,123 -1.3% 2.04% $196.0M 2025-05-15 $253.28
2024 Q4 REDUCED — — — 783,309 -11,370 -1.4% 1.78% $183.5M 2025-02-14 $261.34
2024 Q3 REDUCED — — — 794,679 -39,712 -4.8% 1.91% $202.9M 2024-11-14 $243.79
2024 Q2 REDUCED 15.9% +7.5% ❌ 834,391 -157,173 -15.9% 1.92% $198.6M 2024-08-14 $235.25
2024 Q1 REDUCED 19.2% +2.2% ❌ 991,564 -234,966 -19.2% 2.22% $229.0M 2024-05-15 $228.31
2023 Q4 REDUCED 12.5% +15.2% ❌ 1,226,530 -175,311 -12.5% 2.56% $243.3M 2024-02-14 $212.11
99 older quarters hidden  —  Sign in free or upgrade to Premium to see full history

🏢 Other funds also holding ECL

As of 2026 Q1 — sorted by position size

WORMSER FRERES GESTION 5.7% MCDONALD CAPITAL INVESTORS INC/CA 3Y 7Y 5.32% Foresight Group Ltd Liability Partnership 4.67% DUDLEY & SHANLEY, INC. 3Y 7Y 4.57% McCollum Christoferson Group LLC 3Y 7Y 3.81% S&CO INC 3Y 7Y 3.73% MCDANIEL TERRY & CO 3Y 7Y 3.71% Mirova US LLC 3Y 3.53% FIRETRAIL INVESTMENTS PTY LTD 3.53% Birch Hill Investment Advisors LLC 3Y 7Y 3.46%

FAQ About MAIRS & POWER INC and ECL

These are the practical questions this page is built to answer before you even open the full history table.

How long has MAIRS & POWER INC reported owning ECL?

MAIRS & POWER INC reported ECL across 9 quarterly 13F filings, from 2023 Q4 through 2025 Q4.

What was the largest reported ECL position in MAIRS & POWER INC's portfolio?

The largest reported portfolio weight for ECL was 2.56% in 2023 Q4.

What is the latest reported ECL position on this page?

The most recent filing on this page is 2025 Q4, when MAIRS & POWER INC reported 770,571 shares, equal to 1.95% of portfolio, with an estimated market value of $202.3M.

What does the chart on this ECL ownership page compare?

The chart compares MAIRS & POWER INC's quarterly ECL portfolio weight with the stock's indexed share price, so you can see whether the fund was building, trimming, or holding the position as price moved.

How well did MAIRS & POWER INC time their ECL position?

Based on 13F filing dates vs. subsequent ECL price moves, MAIRS & POWER INC correctly timed 43 out of 105 reported position changes (41%). The annualised alpha on ECL relative to SPY over the holding period was +3.5%.

← Back to MAIRS & POWER INC Holdings