Comfort Systems USA, Inc.
MX ˙ BMV ˙ US1999081045
SecurityMX:FIX / Comfort Systems USA, Inc.
InstitutionAmerican Century Companies Inc
Latest Disclosed Ownership51,120 shares
Latest Disclosed Value $ 70,493,969
American Century Companies Inc reports 55.19% decrease in ownership of FIX / Comfort Systems USA, Inc.

On May 15, 2026 - American Century Companies Inc filed a 13F-HR form disclosing ownership of 51,120 shares of Comfort Systems USA, Inc. (MX:FIX) valued at $70,493,969 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 114,070 shares of Comfort Systems USA, Inc.. This represents a change in shares of -55.19% 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)
2026-05-15 2026-03-31 13F COMFORT SYS USA COM 199908104 51,120 -62,950 -55.19 70,494 -33.78 0.0363
2026-02-13 2025-12-31 13F COMFORT SYS USA COM 199908104 114,070 7,742 7.28 106,460 21.34 0.0535
2025-11-12 2025-09-30 13F COMFORT SYS USA COM 199908104 106,328 7,293 7.36 87,740 65.22 0.0446
2025-08-12 2025-06-30 13F COMFORT SYS USA COM 199908104 99,035 13,981 16.44 53,104 93.70 0.0289
2025-05-13 2025-03-31 13F COMFORT SYS USA COM 199908104 85,054 6,015 7.61 27,415 -18.21 0.0168
2025-02-11 2024-12-31 13F COMFORT SYS USA COM 199908104 79,039 22,116 38.85 33,517 50.85 0.0193
2024-11-12 2024-09-30 13F COMFORT SYS USA COM 199908104 56,923 799 1.42 22,220 30.18 0.0129
2024-08-07 2024-06-30 13F COMFORT SYS USA COM 199908104 56,124 26,752 91.08 17,068 82.92 0.0104
2024-05-14 2024-03-31 13F COMFORT SYS USA COM 199908104 29,372 -27,910 -48.72 9,332 -20.80 0.0059
2024-02-13 2023-12-31 13F COMFORT SYS USA COM 199908104 57,282 13,774 31.66 11,781 58.90 0.0081
2023-11-13 2023-09-30 13F COMFORT SYS USA COM 199908104 43,508 18,933 77.04 7,414 83.74 0.0058
2023-08-14 2023-06-30 13F COMFORT SYS USA COM 199908104 24,575 17,838 264.78 4,035 320.31 0.0030
2023-05-11 2023-03-31 13F COMFORT SYS USA COM 199908104 6,737 1,426 26.85 960 57.12 0.0008
2023-02-13 2022-12-31 13F COMFORT SYS USA COM 199908104 5,311 1,352 34.15 611 58.70 0.0005
2022-11-14 2022-09-30 13F COMFORT SYS USA COM 199908104 3,959 -934 -19.09 385 -5.41 0.0003
2022-08-12 2022-06-30 13F COMFORT SYS USA COM 199908104 4,893 -10,353 -67.91 407 -70.01 0.0003
2022-05-11 2022-03-31 13F COMFORT SYS USA COM 199908104 15,246 -1,200 -7.30 1,357 -16.59 0.0009
2022-02-07 2021-12-31 13F COMFORT SYS USA COM 199908104 16,446 795 5.08 1,627 45.79 0.0010
2021-11-10 2021-09-30 13F COMFORT SYS USA COM 199908104 15,651 5,852 59.72 1,116 44.56 0.0008
2021-08-05 2021-06-30 13F COMFORT SYS USA COM 199908104 9,799 1,218 14.19 772 20.25 0.0005
2021-05-14 2021-03-31 13F COMFORT SYS USA COM 199908104 8,581 1,642 23.66 642 75.89 0.0005
2021-02-12 2020-12-31 13F COMFORT SYS USA COM 199908104 6,939 947 15.80 365 18.12 0.0003
2020-11-13 2020-09-30 13F COMFORT SYS USA COM 199908104 5,992 5,992 309 0.0003
2020-08-13 2020-06-30 13F COMFORT SYS USA COM 199908104 0 -21,424 -100.00 0 -100.00
2020-05-14 2020-03-31 13F COMFORT SYS USA COM 199908104 21,424 -12,460 -36.77 783 -53.64 0.0009
2020-02-12 2019-12-31 13F COMFORT SYS USA COM 199908104 33,884 -118,384 -77.75 1,689 -74.92 0.0016
2019-11-13 2019-09-30 13F COMFORT SYS USA COM 199908104 152,268 -18,748 -10.96 6,735 -22.76 0.0068
2019-08-14 2019-06-30 13F COMFORT SYS USA COM 199908104 171,016 26,185 18.08 8,720 14.92 0.0087
2019-05-14 2019-03-31 13F COMFORT SYS USA COM 199908104 144,831 4,165 2.96 7,588 23.50 0.0077
2019-02-12 2018-12-31 13F COMFORT SYS USA COM 199908104 140,666 140,666 6,144 0.0070
2017-11-01 2017-09-30 13F COMFORT SYS USA COM 199908104 0 -7,125 -100.00 0 -100.00
2017-08-07 2017-06-30 13F COMFORT SYS USA COM 199908104 7,125 7,125 264 0.0003
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.