Watsco, Inc.
US ˙ NYSE ˙ US9426222009 ˙ Waste Management

SecurityWSO / Watsco, Inc.
InstitutionMattern Capital Management, Llc
Latest Disclosed Ownership3,594 shares
Latest Disclosed Value $ 1,497,728
Mattern Capital Management, Llc reports 0.55% decrease in ownership of WSO / Watsco, Inc.

On July 24, 2026 - Mattern Capital Management, Llc filed a 13F-HR form disclosing ownership of 3,594 shares of Watsco, Inc. (US:WSO) valued at $1,497,728 USD as of June 30, 2026. The entity filed a previous 13F-HR on May 4, 2026 disclosing 3,614 shares of Watsco, Inc.. This represents a change in shares of -0.55% during the quarter. The current value of the position is $1,133,476 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-07-24 2026-06-30 13F WATSCO COM 942622200 3,594 -20 -0.55 1,498 13.93 0.1748
2026-05-04 2026-03-31 13F WATSCO COM 942622200 3,614 389 12.06 1,315 20.99 0.1575
2026-01-29 2025-12-31 13F WATSCO COM 942622200 3,225 1,073 49.86 1,087 24.83 0.1283
2025-10-21 2025-09-30 13F WATSCO COM 942622200 2,152 626 41.02 870 29.27 0.1023
2025-07-21 2025-06-30 13F WATSCO COM 942622200 1,526 308 25.29 674 8.72 0.0810
2025-04-23 2025-03-31 13F WATSCO COM 942622200 1,218 58 5.00 619 12.75 0.0788
2025-02-03 2024-12-31 13F WATSCO COM 942622200 1,160 51 4.60 550 0.73 0.0716
2024-10-24 2024-09-30 13F WATSCO COM 942622200 1,109 105 10.46 545 17.20 0.0687
2024-08-02 2024-06-30 13F WATSCO COM 942622200 1,004 185 22.59 465 31.73 0.0643
2024-05-14 2024-03-31 13F WATSCO COM 942622200 819 819 354 0.0480
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.