Institutions Shift Positions Across Key U.S. Stocks

Recent regulatory filings show a series of sizable portfolio moves by large asset managers across technology, life sciences and industrial names. William Blair Investment Management LLC and TD Asset Management Inc reported significant changes in holdings in companies including IDEXX Laboratories (IDXX), Teradyne, Bio-Techne, Tyler Technologies, BWX Technologies and DexCom.

These shifts come alongside fresh quarterly earnings, updated guidance and new analyst targets, offering a snapshot of how institutional capital and Wall Street research are responding to company-specific developments.

William Blair Investment Management cut its stake in IDEXX Laboratories (IDXX) by 33.0% in the third quarter, selling 226,069 shares and ending the period with 459,019 shares worth $293.3 million, or about 0.57% of the company. IDEXX still represented roughly 0.8% of William Blair’s portfolio as its 23rd largest holding.

Over the same quarter, William Blair established a new position in Teradyne, purchasing 775,463 shares valued at about $106.7 million and representing roughly 0.50% of Teradyne. It also lifted its stake in Bio-Techne by 75.9% to 1,709,662 shares, or about 1.10% of the biotechnology company, worth $95.1 million.

In Tyler Technologies, William Blair increased its holdings by 28.1% to 459,114 shares, or 1.07% of the company, valued at $240.2 million. By contrast, it reduced its position in BWX Technologies by 17.3%, ending the quarter with 1,255,310 shares, or 1.37% of the stock, worth $231.4 million.

Several of the companies experiencing portfolio shifts also reported recent earnings. IDEXX Laboratories (IDXX) posted quarterly earnings per share of $2.92 on revenue of $1.09 billion, up 14.3% year over year, and issued FY 2026 EPS guidance of $14.29 to $14.80.

Teradyne reported EPS of $1.80, beating consensus estimates by $0.44, on revenue of $1.08 billion, up 43.9% from a year earlier. Analysts as a group expect Teradyne to post full-year EPS of 3.88. BWX Technologies delivered EPS of $1.08 versus a $0.91 consensus on revenue of $885.84 million, an 18.7% annual increase, and set FY 2026 guidance at $4.55 to $4.70 EPS.

Bio-Techne reported EPS of $0.46, three cents above expectations, on revenue of $295.88 million, down 0.4% from the prior year. Becton, Dickinson and Company, another name with notable institutional activity, posted EPS of $2.91, topping estimates by $0.10, on revenue of $5.25 billion, up 1.6% year over year, and issued FY 2026 EPS guidance of $12.35 to $12.65.

TD Asset Management Inc expanded its position in Teradyne by 237.4% during the third quarter, adding 108,933 shares to reach 154,813 shares valued at $21.3 million, or about 0.10% of the company. It also increased its stake in DexCom by 16.2% to 320,798 shares, representing approximately 0.08% of the medical device maker and worth $21.6 million.

DexCom recently reported quarterly EPS of $0.68, above the $0.65 consensus, on revenue of $1.26 billion, 13.1% higher than a year earlier. Analysts collectively forecast full-year EPS of 2.03.

Across the highlighted companies, recent insider activity has included share sales by executives at IDEXX, Teradyne, BWX Technologies and Becton, Dickinson, and a purchase by an insider at Tyler Technologies. For example, IDEXX executives George Fennell and Michael G. Erickson sold a combined 16,716 shares in February, while BWX Technologies’ CEO Rex D. Geveden sold 10,000 shares.

Analyst coverage remains broadly constructive. IDEXX, Teradyne, Bio-Techne, Tyler Technologies, BWX Technologies and DexCom each carry a consensus rating of “Moderate Buy” based on MarketBeat data. Becton, Dickinson holds an overall “Hold” rating, with a consensus price target of $195.46.