AMENTUM HOLDINGS INC

Ticker: AMTM CUSIP: 023939101 Class: COM

PRIMECAP MANAGEMENT CO/CA/'s Holding History (CIK: 0000763212)

Note: Option positions (PUT/CALL) are excluded.

Q4 2025

Shares 12,126,927 Value ($000) $351,681 Avg Close $25.56 Range $21.11 - $31.87

Q3 2025

Shares 11,918,586 Value ($000) $285,450 Avg Close $24.35 Range $21.71 - $26.63

Q2 2025

Shares 12,030,656 Value ($000) $284,044 Avg Close $20.90 Range $16.01 - $24.33

Q1 2025

Shares 10,061,589 Value ($000) $183,121 Avg Close $20.37 Range $16.95 - $24.30

Q4 2024

Shares 6,414,379 Value ($000) $134,894 Avg Close $25.85 Range $18.38 - $34.47

Q3 2024

Shares 5,271,282 Value ($000) $169,999 Avg Close $28.49 Range $23.58 - $34.50

Period	Shares	Value ($000)	Average Close	Price Range
Q4 2025	12,126,927	$351,681	$25.56	$21.11 - $31.87
Q3 2025	11,918,586	$285,450	$24.35	$21.71 - $26.63
Q2 2025	12,030,656	$284,044	$20.90	$16.01 - $24.33
Q1 2025	10,061,589	$183,121	$20.37	$16.95 - $24.30
Q4 2024	6,414,379	$134,894	$25.85	$18.38 - $34.47
Q3 2024	5,271,282	$169,999	$28.49	$23.58 - $34.50