Comfort Systems USA, Inc.
US ˙ NYSE ˙ US1999081045

SecurityFIX / Comfort Systems USA, Inc.
InstitutionMarshall Wace, Llp
Latest Disclosed Ownership2,079 shares
Latest Disclosed Value $ 2,866,920
Marshall Wace, Llp ownership in FIX / Comfort Systems USA, Inc.

On May 14, 2026 - Marshall Wace, Llp filed a 13F-HR form disclosing ownership of 2,079 shares of Comfort Systems USA, Inc. (US:FIX) valued at $2,866,920 USD as of March 31, 2026. The entity filed a previous 13F-HR on August 13, 2025 disclosing 0 shares of Comfort Systems USA, Inc.. The current value of the position is $3,846,233 USD.

Marshall Wace, Llp has a history of taking positions in derivatives of the underlying security (FIX) in the form of stock options.

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.

Upgrade to unlock premium data and export to Excel .

Institutional Put/Call Ratios
(Premium Subscription Required)

In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

FIX / Comfort Systems USA, Inc. Historical Put/Call Ratio
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)
2026-05-14 2026-03-31 13F COMFORT SYSTEMS COMMON STOCK 199908104 2,079 2,079 2,867 0.0014
2025-08-13 2025-06-30 13F COMFORT SYSTEMS COMMON STOCK 199908104 0 -51,254 -100.00 0 -100.00
2025-05-15 2025-03-31 13F COMFORT SYSTEMS COMMON STOCK 199908104 51,254 50,725 9,588.85 16,521 7,275.00 0.0210
2025-02-13 2024-12-31 13F COMFORT SYSTEMS COMMON STOCK 199908104 529 529 224 0.0003
2020-08-13 2020-06-30 13F COMFORT SYSTEMS COMMON STOCK 199908104 0 -33,687 -100.00 0 -100.00
2020-05-15 2020-03-31 13F COMFORT SYSTEMS COMMON STOCK 199908104 33,687 -77,638 -69.74 1,231 -77.82 0.0123
2020-02-14 2019-12-31 13F COMFORT SYSTEMS COMMON STOCK 199908104 111,325 -17,491 -13.58 5,550 -2.60 0.0381
2019-11-14 2019-09-30 13F COMFORT SYSTEMS COMMON STOCK 199908104 128,816 128,816 5,698 0.0448
2019-05-14 2019-03-31 13F COMFORT SYSTEMS COMMON STOCK 199908104 0 -99,703 -100.00 0 -100.00
2019-02-14 2018-12-31 13F COMFORT SYSTEMS COMMON STOCK 199908104 99,703 99,703 4,355 0.0445
2016-11-10 2016-09-30 13F COMFORT SYSTEMS COMMON STOCK 199908104 0 -66,739 -100.00 0 -100.00
2016-08-12 2016-06-30 13F COMFORT SYSTEMS COMMON STOCK 199908104 66,739 10,245 18.13 2,174 21.11 0.0183
2016-05-13 2016-03-31 13F COMFORT SYSTEMS COMMON STOCK 199908104 56,494 56,494 0.00 1,795 0.0173
2016-02-10 2015-12-31 13F COMFORT SYSTEMS COMMON STOCK 199908104 0 0 0 0.0000
2015-11-12 2015-09-30 13F COMFORT SYSTEMS COMMON STOCK 199908104 0 -22,865 -100.00 0 -100.00
2015-08-14 2015-06-30 13F COMFORT SYSTEMS COMMON STOCK 199908104 22,865 22,865 525 0.0068
Disclosed Put Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share Price Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2025-05-15 2025-03-31 13F COMFORT SYSTEMS EQUITY OPTION Put 0 -100.00 0 -100.00 n/a n/a n/a
2025-02-13 2024-12-31 13F COMFORT SYSTEMS EQUITY OPTION Put 31,600 13,400 n/a n/a n/a
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.