On October 15, 2025, Harbor Capital Advisors reported selling 34,799 shares of Comfort Systems USA (FIX -1.47%), an estimated $23.58 million trade based on quarterly average pricing.
What happened
According to a filing with the Securities and Exchange Commission dated October 15, 2025, Harbor Capital Advisors reduced its holdings in Comfort Systems USA (FIX -1.47%) by 34,799 shares during Q3 2025.
The estimated value of the shares sold was approximately $23.58 million, calculated using the average closing price over Q3 2025. The fund reported holding 9,286 shares, worth $7.66 million.
What else to know
This sale reduced the position to 0.6% of 13F assets under management, moving it outside the fund’s top five holdings.
Harbor Capital’s top holdings after the filing:
- iShares Core S&P 500 ETF: $49.15 million (3.8% of AUM)
- iShares MSCI Emerging Markets ETF: $38.43 million (3.0% of AUM)
- iShares MSCI EAFE ETF: $28.28 million (2.2% of AUM)
- Nvidia: $27.22 million (2.1% of AUM)
- Alphabet: $26.54 million (2.1% of AUM)
As of October 14, 2025, shares of Comfort Systems USA were priced at $831.89, up 98% over the past year, outperforming the S&P 500 by 87 percentage points over that time.
Company overview
| Metric | Value |
|---|---|
| Revenue (TTM) | $7.68 billion |
| Net Income (TTM) | $692.24 million |
| Dividend Yield | 0.20% |
| Price (as of market close October 14, 2025) | $831.89 |
Company snapshot
Comfort Systems USA:
- Provides mechanical, electrical, and plumbing (MEP) installation, renovation, maintenance, and repair services, with a focus on HVAC, electrical, plumbing, piping, controls, and fire protection systems.
- Generates revenue through project-based contracting for new construction, retrofits, and ongoing maintenance agreements, leveraging technical expertise and integrated service offerings.
- Serves commercial, industrial, and institutional customers such as building owners, developers, general contractors, architects, consulting engineers, and property managers across the United States.
Comfort Systems USA provides mechanical, electrical, and plumbing services at scale for commercial and institutional clients.
Foolish take
Over the last two years, Harbor Capital grew its portfolio allocation in Comfort Systems USA from 0.1% to 1%. In that time, the stock nearly tripled, so it makes a lot of sense that the firm would pare its position down now.
In fact, Comfort Systems’ stock is up 135% in just the last six months alone, so Harbor Capital may just be capitalizing on this incredible run while rebalancing its portfolio.
To put this stock price ascension in perspective, consider that even though the firm sold three-quarters of its FIX stake, its portfolio allocation only dropped from 1% to 0.6% since the stock rose so much.
From a longer-term, Foolish perspective, there is a lot to like about Comfort Systems’ business. Its MEP services currently sit at the center of three megatrends in the United States: the data center boom, the chip manufacturing buildout, and the onshoring of similar industries moving back to the U.S.
Powered by these trends, the company’s backlog has nearly quadrupled since 2021, and its stock has reacted accordingly.
However, as promising as Comfort Systems’ business is, its stock now trades at 42 times earnings — its highest level since 2011.
That said, if the stock keeps growing sales by 35% like it has in the last year, it could quickly outgrow what looks like a lofty valuation. Comfort Systems USA is a great stock for investors interested in the space to monitor.
Glossary
13F reportable assets: Assets that institutional investment managers must report quarterly to the SEC, disclosing certain equity holdings.
Assets under management (AUM): The total market value of investments managed on behalf of clients by a fund or firm.
Quarterly average pricing: The average price of a security over a specific quarter, used for valuation or reporting purposes.
Top holdings: The largest investments in a fund’s portfolio, typically ranked by market value or portfolio weight.
Dividend yield: A financial ratio showing how much a company pays in dividends each year relative to its share price.
Mechanical, electrical, and plumbing (MEP): Building systems involving mechanical, electrical, and plumbing components, essential for construction and facility operations.
HVAC: Heating, ventilation, and air conditioning systems used for regulating indoor climate and air quality.
Retrofits: Upgrades or modifications to existing buildings or systems to improve performance or efficiency.
Maintenance agreements: Contracts for ongoing service and upkeep of equipment or systems, often providing recurring revenue.
Institutional customers: Organizations such as businesses, governments, or nonprofits that purchase goods or services, as opposed to individual consumers.
General contractors: Companies responsible for overseeing and managing construction projects, including hiring subcontractors and coordinating work.
TTM: The 12-month period ending with the most recent quarterly report.