Comfort Systems USA, Inc.
MX ˙ BMV ˙ US1999081045
SecurityMX:FIX / Comfort Systems USA, Inc.
InstitutionAssenagon Asset Management S.A.
Latest Disclosed Ownership15,158 shares
Latest Disclosed Value $ 20,902,730
Assenagon Asset Management S.A. reports 50.93% increase in ownership of FIX / Comfort Systems USA, Inc.

On April 20, 2026 - Assenagon Asset Management S.A. filed a 13F-HR form disclosing ownership of 15,158 shares of Comfort Systems USA, Inc. (MX:FIX) valued at $20,902,730 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 9, 2026 disclosing 10,043 shares of Comfort Systems USA, Inc.. This represents a change in shares of 50.93% during the quarter.

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)
2026-04-20 2026-03-31 13F COMFORT SYS USA COM 199908104 15,158 5,115 50.93 20,903 123.00 0.0317
2026-01-09 2025-12-31 13F COMFORT SYS USA COM 199908104 10,043 -23,408 -69.98 9,373 -66.04 0.0129
2025-10-07 2025-09-30 13F COMFORT SYS USA COM 199908104 33,451 -27,895 -45.47 27,603 -16.09 0.0377
2025-07-11 2025-06-30 13F COMFORT SYS USA COM 199908104 61,346 60,557 7,675.16 32,894 12,850.39 0.0488
2025-04-15 2025-03-31 13F COMFORT SYS USA COM 199908104 789 -10,501 -93.01 254 -94.69 0.0004
2025-01-14 2024-12-31 13F COMFORT SYS USA COM 199908104 11,290 -5,117 -31.19 4,788 -25.25 0.0077
2024-10-23 2024-09-30 13F COMFORT SYS USA COM 199908104 16,407 11,213 215.88 6,404 305.57 0.0118
2024-07-18 2024-06-30 13F COMFORT SYS USA COM 199908104 5,194 2,073 66.42 1,580 59.33 0.0035
2024-04-24 2024-03-31 13F COMFORT SYS USA COM 199908104 3,121 -60,354 -95.08 992 -92.41 0.0023
2024-01-17 2023-12-31 13F COMFORT SYS USA COM 199908104 63,475 -55,697 -46.74 13,055 -35.72 0.0347
2023-11-06 2023-09-30 13F COMFORT SYS USA COM 199908104 119,172 -20,389 -14.61 20,308 -11.38 0.0629
2023-07-25 2023-06-30 13F COMFORT SYS USA COM 199908104 139,561 -19,876 -12.47 22,916 -1.53 0.0793
2023-04-18 2023-03-31 13F COMFORT SYS USA COM 199908104 159,437 27,250 20.61 23,271 155,040.00 0.0826
2023-01-12 2022-12-31 13F COMFORT SYS USA COM 199908104 132,187 132,187 15 0.0549
2022-04-25 2022-03-31 13F COMFORT SYS USA COM 199908104 0 -30,845 -100.00 0 -100.00
2022-02-01 2021-12-31 13F COMFORT SYS USA COM 199908104 30,845 14,220 85.53 3,052 157.34 0.0088
2021-10-19 2021-09-30 13F COMFORT SYS USA COM 199908104 16,625 971 6.20 1,186 -3.81 0.0038
2021-07-15 2021-06-30 13F COMFORT SYS USA COM 199908104 15,654 15,654 1,233 0.0042
2021-02-01 2020-12-31 13F COMFORT SYS USA COM 199908104 0 -41,400 -100.00 0 -100.00
2020-10-07 2020-09-30 13F COMFORT SYS USA COM 199908104 41,400 -530 -1.26 2,133 24.81 0.0120
2020-07-21 2020-06-30 13F COMFORT SYS USA COM 199908104 41,930 41,930 1.28 1,709 -19.88 0.0110
2020-01-17 2019-12-31 13F COMFORT SYS USA COM 199908104 0 -107,570 -100.00 0 -100.00
2019-10-16 2019-09-30 13F COMFORT SYS USA COM 199908104 107,570 80,540 297.97 4,758 245.28 0.0319
2019-08-12 2019-06-30 13F COMFORT SYS USA COM 199908104 27,030 -104,604 -79.47 1,378 -80.02 0.0104
2019-04-26 2019-03-31 13F COMFORT SYS USA COM 199908104 131,634 124,214 1,674.04 6,896 2,028.40 0.0647
2019-01-23 2018-12-31 13F COMFORT SYS USA COM 199908104 7,420 -173,787 -95.91 324 -96.83 0.0037
2018-10-29 2018-09-30 13F COMFORT SYS USA COM 199908104 181,207 181,207 2,342.14 10,220 3,054.32 0.1009
2018-07-17 2018-06-30 13F COMFORT SYS USA COM 199908104 0 -20,912 -100.00 0 -100.00
2018-04-30 2018-03-31 13F COMFORT SYS USA COM 199908104 20,912 -80,501 -79.38 863 -80.51 0.0112
2018-01-25 2017-12-31 13F COMFORT SYS USA COM 199908104 101,413 101,413 4,427 0.0456
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.